Cheap PCs with a Linux operating system seem to have hit users' sweet spots, with taking the plunge into the alternate OS now considered not nearly as difficult as users had thought.

Linux is not just for computer whizzes. In fact, buying Linux and learning how to use it are easier than ever, thanks to the open source operating system's expanding presence in affordable computers and mainstream retail outlets.

In quick succession, the number of mass market, sub US$200 desktops has tripled -- from one to three -- in less than three months. At the Consumer Electronics Show in Las Vegas earlier this month, small form-factor PC maker Shuttle debuted its US$199 KPC. The catch? It's not preloaded with Windows, but an operating system based on Linux. Then last week, Mirus and Linspire collaborated on the Mirus Linux PC, which is now for sale at Sears.com. It's US$299 (although an included US$100 rebate brings it to US$199), and is preloaded with Freespire 2.0, an Ubuntu-based Linux distribution.

But the beginning of the low cost computer trend actually started last spring. The Everex gPC showed up on the shelves of Wal-Mart for US$198, a low price even for a desktop PC. It's bundled with speakers, a mouse, and a keyboard, and it comes with 24 hour tech support. The operating system is called gOS, a version of Ubuntu 7.10. Sure, that may be almost unpronounceable for most average consumers, but despite that, Wal-Mart is having trouble keeping the gPC in stock.

Linux is getting more mainstream exposure than just appearing in inexpensive computers. It's now being offered by two of the world's largest PC manufacturers, Dell and Lenovo, and is making its way into tiny -- not to mention trendy -- inexpensive laptops, like One Laptop Per Child's XO, Everex's CloudBook, and Asus' Eee PC, all of which come with Linux preinstalled. In the case of the Eee, it is doing surprisingly well with consumers.

So what are we to think now that Linux, long popular among a very narrow niche of computer users, is making its way to mainstream retail outlets? Perhaps that trying a US$200 Linux PC isn't as risky as some might think. Here are five reasons why.

Lower barrier to entry
At US$200, that's not a huge penalty for trying an unfamiliar operating system packaged by a hardware company you may not have heard of before. Just to put it in proper perspective, US$199 is less than half the price of an iPhone, and is roughly equivalent to about five percent of the cost of a new decent-quality 32-inch high-definition TV or five to six tanks of petrol. If you don't have a ton of expendable income, you can always put off updating your current Windows or Mac machine for six months, try it out, and see what you think.

Preinstalled is perfect for newbies
True, the biggest headache associated with most versions of Linux these days is the actual installation, but that's the case for any operating system, Stephen O'Grady, principal analyst for Redmonk, points out. Installing Windows from scratch on a machine can hit snags just as much as installing a version of Linux. But, he added: "If you're getting it preinstalled, the manufacturer has done the legwork to make sure the individual parts in the machine work with the operating system involved." All of that can translate to fewer headaches for the user.

And maintenance is relatively easy. That's because most versions of Linux come with package management. Unlike Windows, which just updates the operating system itself, Ubuntu, for example, will update the OS plus any of the applications included. "The average everyday user doesn't have to do anything," O'Grady said.

Familiarity breeds loyalty
Linux is getting easier to use all the time -- and better looking. The past two years have seen the most consistent leaps in the improvement of the user interface. In the last year alone, 3D desktop effects -- a la Windows Vista and Mac OS X -- have been introduced.

"There has been some effort in recent years to make the transition more comfortable by mimicking some of the user conventions of Windows or Mac OS," said O'Grady. For instance, a "Start" menu or an applications "dock." The Everex Green PC runs gOS, whose desktop looks strikingly similar to Mac OS X.

The specs are acceptable for general use
All of the companies making sub US$200 Linux machines -- Everex, Shuttle, and Mirus -- use brand-name parts you've heard of: Intel processors and chipsets; ATI graphics cards; and more. Mirus' and Shuttle's Linux PCs come with a minimum of 1GB of memory, and Everex's comes with 512MB, upgradable to 2GB. All three have an 80GB hard drive, enough to do basic computing tasks. It should be noted that none of the offerings is a complete PC, however. The gPC and the Mirus lack a monitor, and the Shuttle comes with nothing but the PC.

The Web browser is your friend
It sounds simple, but most of what the average user wants to do with a computer these days can be done online: word processing, spreadsheets, e-mail, photo editing, and more, which means less storage is less of an issue. You want e-mail? Gmail and the included GTalk instant messaging feature are free. And Google's Docs and Spreadsheets Web apps get all of your office productivity done online (though most of the three PCs have open source versions of Microsoft Office). For watching videos, there's YouTube and Hulu.com. And rather than downloading a photo editing tool, anyone can upload their photos to Flickr and use Picnik's editing software right in the browser.

The success of devices like the gPC and Mirus Freespire -- both are sold out at Wal-Mart and Sears.com, respectively -- and even the more expensive and portable Eee PC, is a surprise to most.

"The success is, in part, driven by the fact that for people doing an increasing percentage of day-to-day tasks like e-mail in the context of software as a service, at that point it soon doesn't matter what operating system you have," said Redmonk's O'Grady. "If a majority of [computer] usage is browsing the Internet and doing things like that, [Linux] is perfectly credible, perfectly usable."