That is changing. A new miniature-chip technology from Texas Instruments (TXN) called pico is making digital projectors truly portable, instead of merely luggable. For the past couple of weeks, I’ve been using two of the first pico-based projectors on the market, Dell’s M109S and Optoma’s Pico PK-101.

The products are designed for different customers with different needs. Dell (DELL) positions the 13-ounce M109S as a notebook companion, best suited for work presentations. The four-ounce Optoma projector is designed more as an iPod or digital-camera accessory for watching movies and slide shows on the go.

The Dell M109S

Their portability requires compromises, most obviously in brightness and image resolution. The Dell and Optoma projectors, respectively, support 11 and 50 lumens — a standard measure of projector brightness. That’s far dimmer than top-notch projectors that offer several thousand lumens. So neither product excels in well-lighted rooms, where overhead and ambient lighting overpower their images. You can compensate somewhat for this weakness by placing the devices closer to the surfaces onto which they’re projecting — for example, a wall. But the darker the room you use, the better.

At about the size of a candy bar, the $399 Optoma device is the smaller of the two projectors and the one with the most intriguing possibilities for expanding the tiny screen sizes of mobile devices like the iPod.

It’s powered by a rechargeable battery that Optoma says lasts for an hour on full brightness or two hours on a power-saving setting (the projector comes with two batteries). The projector has a tiny speaker, but people who want decent sound will need to use headphones or external speakers.

In theory, the Optoma device is small enough to bring along on a camping trip to show a film on the side of a tent, or to a restaurant, where you could inflict a vacation slide show on dinner mates by projecting onto a napkin or tablecloth.

I tested it on a recent airplane flight by projecting an episode of “Mad Men” from an iPod touch onto the back of the seat in front of me. The seat was a dark blue with embossing on it, so it didn’t work very well. It’s best to project onto an unmarked, light-colored surface. The quality of the image was better when I lay in bed one night, projecting a video onto a white ceiling.

Even under the most favorable circumstances, however, I found the images from the Optoma projector very dark, muddling the outlines of characters and action on screen. Although Optoma says you can get up to a 60-inch image from the projector, 45 inches was about as big as I could make the image before it got too fuzzy.

Optoma says the projector will ship with an iPod-compatible connector cable when it goes on sale in the U.S. on Dec. 15, though the unit I tested didn’t come with one. I connected the device to my iPod touch using a $50 cable from Apple (AAPL).

Compared with the Optoma device, the $449 Dell M109S is a behemoth, yet it’s still only about the size of a short stack of drink coasters. Most projectors weigh at least a few pounds, if not more, which is big enough to make them a hassle to carry around. I barely noticed the Dell projector inside my laptop bag.

Unlike the Optoma projector, the Dell M109S has to be plugged into an electrical outlet to work. It comes with an unsightly set of connectors for plugging the projector into a video source, such as the VGA port found on most laptops and a composite video plug that is standard on DVD players. I was, however, able to plug my iPod touch into the Dell projector using the $50 Apple cable.

And unlike the Optoma, the Dell doesn’t have speakers. To get sound for a movie, you’ll need headphones or speakers, like those on a laptop.

Despite its extra bulk, the Dell M109S literally outshines the Optoma projector. It produces a bright image that I found very watchable, even if it wasn’t high-definition. I projected the movie “James and the Giant Peach” onto an interior wall of my house, creating an image that was about 7 feet, measured diagonally.

The Dell M109S includes a capability called keystone correction, a standard feature in most projectors that adjusts a projected image to give it the proper dimensions, rather than the trapezoidal shape that results when a projector is angled upward. The Optoma projector doesn’t have this feature. To get a normal rectangular movie image, I had to hold the projector level, toward the projection surface.

For business travelers who do presentations or for people who want to create a theater-like experience in a hotel room, vacation house or against a sheet in the backyard, the Dell projector would be a good fit. For now, the Optoma projector is a good idea that needs refinement.

• Email Nick.Wingfield@wsj.com. Walt Mossberg is on vacation.

People today use the Netflix service on their computers, but Netflix (NFLX) has cut a series of deals with hardware partners to make the service available on TV sets through an array of devices.

Most of these devices were designed to do other things: a videogame console, high-definition Blu-ray disc players, a TiVo (TIVO) digital video recorder. So to see how well the service works on these devices, I’ve spent the past couple of weeks comparing the Netflix experience on Microsoft’s (MSFT) Xbox 360 game console, on LG Electronics’ BD300 Blu-ray disc player and on a set-top box from Roku called the Netflix Player. The last, as the name implies, is designed mainly for Netflix service.

The devices suffer from a relatively skimpy selection of videos on the Netflix Internet service. Netflix has more than 100,000 titles for rent on disc, but about 12,000 titles for viewing through its Internet service at the moment, and there’s often a months-long delay after a movie’s release before it shows up online. Television shows generally turn up more quickly, with a handful, like NBC’s “Heroes,” watchable the day after they air.

Still, I find the Netflix service very appealing, especially for catching up on episodes of TV series, such as “30 Rock,” that I missed when they aired. Unlike the iTunes Store and other sites that charge users $1.99 per TV episode and $3.99 to rent a movie online, the Netflix Internet service is free to subscribers to its DVD service on one of the company’s “unlimited” rental plans, which start at $8.99 a month.

Depending on how fast your Internet connection is, Netflix videos begin playing almost instantly, though you can’t keep permanent copies.

Connecting the devices to Netflix through my wired home network was easy in all three cases. I used a wireless home network — more common in homes than the wired variety — with the Roku device, the only one of three products that comes with built-in Wi-Fi (it worked well in this mode). People who want to use the Xbox 360 with a wireless network will have to spend $70 or so on an external Wi-Fi adapter. LG recommends people use only a wired home network to connect to Netflix from its player, including adapter kits that cost about $100 for transmitting data over home power lines.

All the devices require you to create a list of movies you want to watch from a computer, just like Netflix subscribers set up “queues” of DVDs to be delivered by mail. The Xbox 360 offered by far the most elegant-looking interface for browsing through videos in my Netflix queue, letting me glide through a long row of cover art representing the movies and TV shows I selected on my PC.

In contrast, the Netflix menu on the LG Blu-ray player and Roku device were more static, making it more awkward to navigate the expanse of titles. Netflix became available on the Xbox 360 in November as part of a more sweeping software upgrade, delivered over the Internet, that remade the graphical look of the system.

The quality of most of the videos on Netflix is, to my eyes, about DVD quality, though Netflix is adding some titles in high-definition to its Internet library. HD titles were available for viewing only through the Xbox 360 when I was testing the service. Roku and LG say they will make software updates available online this month that add HD support to their devices.

The Xbox 360 also has some annoying quirks when using it as a movie player — including a noisy fan I found distracting. The game controller that comes with the Xbox 360 is clunky for playing movies, so users will need to invest in an inexpensive additional remote-control design for media. The Roku and LG players, in contrast, were totally silent and had acceptable remote controls for watching Netflix videos.

I experienced the most serious glitches with the LG Blu-ray player, which occasionally dropped the video signal to my television set as I was watching a movie. LG says the loss of video signal could have been due to the connection I used to hook the player to my TV, though I’ve never had a problem with other devices using the same connection. The LG Blu-ray player also took the longest of all the devices to install software upgrades from the Internet.

While there are some differences in the Netflix experience on the Roku device, Xbox 360 and LG Blu-ray player, none of them is so great that they should trump other considerations — like a desire to play videogames or watch HD Blu-ray movies — in deciding which system is the best fit.

The LG Blu-ray player is available online for about $300. The cheapest Xbox 360 model is $199. (To get Netflix through the Xbox 360, users must be “gold” members to the $49.99-a-year Xbox Live game service.) But if what you’re after is primarily Netflix movies, and you’ve got room near your TV for another box, the $99.99 Roku product is the best value.

Walt Mossberg is on vacation.

Write to Nick Wingfield at nick.wingfield@wsj.com

Too often, security programs significantly slow down the computer, causing lags in booting up the machine, launching programs and receiving email. Not only that, they can be incredibly annoying, popping up frequent messages or asking questions in techie lingo.

The main screen of the 2009 version of Norton Internet Security is streamlined and even includes a gauge to show much drain the security program is placing on the computer.

Now, Symantec (SYMC) has decided to radically rewrite its main security suite for Windows to directly address these problems. And in my tests, this new product, Norton Internet Security 2009, largely succeeded. It isn’t perfect, but it is the fastest, simplest and least obtrusive security suite I have ever used.

Being quick and quiet is great, but, of course, a security product also has to be effective against the vast number of viruses, spyware programs and other malicious attacks aimed at Windows. I don’t have a security lab in which to test such effectiveness. But PC Magazine does, and the magazine called the new Norton suite’s spyware and virus protection “extremely effective.” The magazine’s tests are described at http://www.pcmag.com/article2/0,2817,2330024,00.asp.

However, I wasn’t impressed with Norton’s optional antispam feature, which caused the only significant problem I ran into in my testing.

The new suite costs $70, and can be purchased at symantec.com and elsewhere. For that price, you get to install it on three PCs and you get a one-year subscription to its updates, which cost $60 thereafter.

Symantec is now including free support, even over the phone, though in my tests this support proved lousy. Norton Internet Security 2009 works only on Windows XP and Windows Vista.

I tested the new security suite on a Dell (DELL) desktop running Vista and on a Macintosh laptop running Windows XP as a “virtual machine,” meaning Windows and Windows programs ran simultaneously with the Mac operating system. Symantec assured me the program would run properly in this latter setup, and I had run the previous version of Norton successfully in the same environment.

The first thing you notice about NIS 2009 is the fast and simple installation. The process took under two minutes on each of my test machines.

File scanning is also much faster, partly because the new suite has a feature called Insight that allows it to skip the scanning and rescanning of many of your files. Insight gathers information about your installed programs and compares them against a list of programs Symantec knows are “trusted,” through either its own research or through scanning results voluntarily submitted by other users. These trusted programs are then exempted from future scans, saving a ton of time.

The new Norton suite has a feature called Insight which calculates how many of your programs it knows are trusted, and therefore needn’t be scanned repeatedly, saving time.

For instance, on my Dell running Vista, an immediate complete scan done before Insight analyzed the computer took more than an hour. But after Insight determined that over 70% of my programs were trusted, complete scans took 10 minutes or less. Of course, your data files, like Word documents and emails, still must be scanned, because they are typically unique.

To minimize the impact on users, the new Norton does scanning and other tasks only when it detects that the computer has been idle for at least 10 minutes. And new virus definitions trickle into your computer invisibly, in the background, rather than all at once in a major process.

Symantec is so certain that its product has a low impact on PC performance that it built a gauge into its new streamlined main screen that shows its drain on the main processor, or CPU.

NIS 2009 is also far less annoying than other suites I’ve used. In normal operation, it notifies you only when it has completed a background task or if there’s a threat or a repair that requires a user action, such as a reboot. And there’s an even quieter optional “silent mode” that can turn off nearly every nonurgent activity of Norton for up to six hours. Silent Mode is automatically activated during full-screen activities, such as playing games or watching movies.

The new suite has a bunch of other features, including a browser toolbar for Internet Explorer and Firefox that warns against fake and malicious Web pages, and that can securely enter your passwords and other information on Web sites. It also has an antispam feature for Microsoft (MSFT) Outlook and Outlook Express.

This antispam feature, which is off by default, was rated as weak by PC Magazine and, in my tests, it caused both Norton and Outlook Express to crash repeatedly in Windows XP running on my Mac. Symantec suspects this is a problem particular to running Windows the way I was on the Mac. After I reinstalled Norton and turned off the feature, all was well again.

But Symantec’s free tech-support service was not only unable to diagnose the problem, it didn’t even know the difference between Outlook and Outlook Express.

Despite this one glitch, I can recommend Norton Internet Security 2009 as a good way to protect your Windows computer with minimal impact on your time and attention.

Find all of Walt Mossberg’s columns and videos online, free, at the All Things Digital Web site, walt.allthingsd.com. Email him at mossberg@wsj.com.

Amazon (AMZN) launched a new service called Amazon Video on Demand, which allows users, for a fee, to watch any of 40,000 TV episodes or movies, in real time, on their Windows and Macintosh computers, and on specially equipped Sony Bravia TV sets. This service replaces an earlier Amazon video offering called Unbox.

I have been testing Amazon Video on Demand and I found it worked well, although it has some limitations. The user interface is clean and smart, the quality is good if you have a fast Internet connection, and there are some clever features. On the downside, it works poorly with the slow connections typical in places like hotels. And there are some studio-imposed limits on what content is offered and how you can view it.

To date, there have been three major models for legally getting TV shows and movies from the Web.

In one, best represented by Apple’s (AAPL) widely used iTunes store, the TV shows and movies are ad-free, but you pay for each. All of this content is downloaded to your Windows or Macintosh computer or your Apple TV set-top box for later viewing, even when you’re not connected to the Internet — though on Apple TV you can start watching while the material is being downloaded.

A second model, best represented by the studio-owned Hulu.com, presents movies and TV shows on a Windows or Macintosh personal computer free of charge, but requires you to watch commercials that can’t be skipped. The TV shows and movies you view on Hulu are “streamed” rather than downloaded, meaning they are meant to be viewed immediately, in real time, rather than stored for viewing when you’re not connected to the Internet.

The third online model is best represented by Netflix (NFLX), the popular DVD distributor. It offers a “Watch Instantly” streaming option on Windows PCs or on TVs equipped with a special set-top box, for a small portion of its large catalog of TV shows and movies. These videos are ad-free and don’t carry an individual charge, but require a monthly subscription fee.

The new Amazon Video on Demand service is a hybrid of these others. As on iTunes, the TV shows and movies it offers are ad-free and purchased individually, don’t require a subscription, and work on both Windows and the Mac, plus on one type of set-top box. In Amazon’s case, that’s Sony’s Bravia Internet Link, a $299 device that works only with Sony (SNE) TVs.

But, like Hulu and Netflix and unlike Amazon’s older Unbox service, the new Amazon Video on Demand service offers videos via real-time streaming. In many cases, it also allows downloading, iTunes-style, to Windows PCs (but not Macs) and to TiVo devices attached to a TV. The videos can’t be streamed in real time using a TiVo (TIVO).

Amazon’s streaming videos are viewed in any of the major Web browsers and don’t require any special software. I tested the new service on both Windows PCs and Macs, and on a Sony Bravia TV equipped with the $299 adapter box. In my tests, Amazon’s videos looked quite good over a fast Internet connection. However, on a typically lousy hotel Internet connection, the movies were often grainy and kept stuttering.

The new service doesn’t yet offer videos in high definition, something Apple just announced this week it is adding for some TV shows. Amazon says it is working on HD.

Amazon’s user interface for the new service is very nice. All of your purchased videos are available in a library stored on the company’s servers, so you can easily watch them again and again if they are purchased, or resume a partly watched rental. And the service remembers where you stopped watching a video and resumes it at that point, even if you started it on, say, a Dell (DELL), and resumed it on a Mac.

On the downside, the new Amazon service isn’t always simple or consistent. For instance, you can watch only two videos at a time, and not all titles can be either streamed and downloaded, or be either purchased or rented. Most rentals last 24 hours, but some differ.

Selection was OK, but not great. Because of studio policies, many current and recent movie hits aren’t available. There are gaps as well in the TV selection. For example, while iTunes offers the current second season of the excellent “Mad Men” series, Amazon has only the first season.

Prices also can be confusing. Amazon rents most movies for $3.99 and sells them for between $9.99 and $14.99. TV shows generally cost $1.99. But some titles carry different prices, albeit these are often lower.

All in all, Amazon Video on Demand is a good service for people who prefer paying for ad-free TV shows and movies, and is another strong step in the Internet’s rising competition with traditional TV.

Find all of Walt Mossberg’s columns and videos online, free, at the All Things Digital Web site, walt.allthingsd.com. Email him at mossberg@wsj.com.

There are two models for this legal Internet distribution. Some shows and movies can be purchased or rented from services like Apple’s iTunes or Amazon’s Unbox. You pay a fee for these downloads, which don’t have commercials, and you can keep any videos you buy to watch repeatedly even without an Internet connection.

The other model, common on the Web sites of the TV networks, is free, ad-supported streaming directly within a Web browser. In this approach, you pay nothing, but you have to watch commercials that can’t be skipped. You must be connected to the Internet while watching, and you don’t get to keep the video.

This week, the ad-supported, streaming approach took a big leap forward with the launch of a Hollywood-backed service called Hulu, at hulu.com. Hulu aims to be a legal, one-stop shop for streaming of TV shows and movies from numerous networks and studios. It’s intended as an attractive antidote to pirate sites and to Google’s YouTube service, which has angered the media companies by allowing users to post all or parts of movies and TV shows without permission or payment.

Hulu is a joint effort of two big media conglomerates, NBC Universal and News Corp., each of which operates multiple networks and studios. (News Corp. also owns The Wall Street Journal and the Web sites where this column is published.) But Hulu contains programming from other companies as well, including Sony and Time Warner. All told, it offers full episodes or clips from about 400 TV series, plus 100 feature films.

I’ve been testing Hulu, and I am very impressed with its design and ease of use, and with the fact that it allows users to edit and re-publish its content on their own sites. Despite some drawbacks, it’s the first Web property I’ve seen from mainstream studios or networks that shows a real understanding of both modern Web design and the Internet’s culture of sharing. In my view, it’s far better than the typical network or studio Web site.

Even though Hulu lacks programming from ABC, CBS and many cable networks, it has a fair selection of popular shows, such as “30 Rock,” “The Office,” “The Simpsons,” “Battlestar Galactica” and “Saturday Night Live.” Its movie catalog includes old favorites like “The Usual Suspects,” “The Big Lebowski” and “Sideways.”

The site is organized in a clean, elegant manner. You can browse shows alphabetically, by genre or by network, or you can use an excellent search system. The search system even brings up links to videos of shows on other sites, such as ABC’s “Grey’s Anatomy,” that are missing from Hulu’s own collection.

Watching the material is a pleasure. You can view it in a fixed window or in full-screen view. You can also “pop out” the viewing window so you can place it anywhere on your screen and resize it to your liking. A feature called “lower lights” grays out everything on the computer screen but the video itself.

Even the advertising is relatively painless. TV shows contain just 25% of the commercial time that’s on regular TV. And Hulu allows you, in some cases, to choose the advertisers whose commercials you see, or else to opt to watch a movie trailer at the start of a video in exchange for seeing no further ads during that viewing.

In a break with Hollywood’s past rigidity, Hulu makes it easy to share, even edit, shows and clips. You can repost an entire video, or any portion of it, on your own blog or on social networking sites.

But Hulu also has some major downsides. Most important, Hulu lacks depth. Even with TV series from its owners’ own networks, Hulu typically contains only a small number of full-length episodes, and mainly offers short clips. In some cases, episodes expire after a while. For some shows, such as “Saturday Night Live,” there aren’t any full episodes, only clips. And the wildly popular “American Idol” isn’t in Hulu at all, even though it airs on News Corp.’s Fox network.

This stands in stark contrast to the depth offered on iTunes, where you can find multiple seasons of full episodes of many shows. And it doesn’t begin to compete with pirate sites, where you can find nearly everything.

Also, Hulu requires a decent broadband connection — a speed of at least 1 megabit per second is recommended, and even higher speeds are needed for some content. That means that using Hulu over the slowest DSL lines or cellphone modem cards will likely provide a poor experience.

Another problem is that, unlike iTunes or Amazon Unbox, Hulu can’t be used via a TV set-top box or a portable player. And shows can’t be saved for offline viewing, such as during flights.

Still, Hulu is a good start for Hollywood in finally providing a better experience for Internet streaming of TV and movies. If the service can add a lot more content and make viewing possible in more scenarios, it might strike a real blow against piracy.

Email me at mossberg@wsj.com. Find all my columns and videos online, free, at the new All Things Digital Web site, http://walt.allthingsd.com.