In the 1998 movie The Truman Show, Truman Burbank was the unwitting star of a round-the-clock reality program televised from a fake ocean-side town inside a multi-billion-dollar dome. Two months ago, Yale graduate Justin Kan attached a wireless video camera to his hat and became the voluntary star of his own always-on webcast, Justin.tv, using just $50,000 in angel funding. And now anyone with a webcam, a computer, and an Internet connection can create his or her own continuous "lifecast"--for free.

Why an individual might wish to do this is a separate matter. But the fact is that thanks to cheap hardware and several new free or low-cost video-streaming services on the Web, the technological and financial barriers to amateur video webcasting--whether one hour per day or 24--are quickly disappearing.

YouTube, blip.tv, Splashcast, and other free video-sharing sites have already created a niche for would-be TV hosts, such as Amanda Congdon, Ze Frank, and William Sledd, who produce quirky video journals in recorded daily installments. The new streaming sites, including Stickam, Ustream, and Veodia, let video artists go live and interactive, sometimes taking their audience's e-mails and phone calls on the air. And at some of these sites, users are taking the plunge into full-time lifecasting.

This week, Kan and his business partners said that they will expand Justin.tv into a lifecasting network open to other live video webcasters. And Ustream, a nine-employee startup in Palo Alto, CA, is running a month-long lifecasting competition among its users; 10 winners, to be announced May 31, will receive broadband wireless cards and 12 months of free wireless streaming, allowing them to roam with their broadcasting gear.

Many critics fail to find the fascination in lifecasting; indeed, much of the time Justin is sleeping or silently working at his computer. "If it were more videogame-like and we could program Justin to run into walls and walk out into traffic, perhaps it would be more entertaining," writes custom publisher and blogger Rex Hammock. But many others seem to enjoy this new genre of voyeurism-by-invitation. Since the launch of Justin.tv on March 19, traffic at the site has surged well past that of established video blogs such as Rocketboom. And Justin is gaining imitators, including technology blogger, podcaster, and LockerGnome founder Chris Pirillo, who started a Ustream lifecast in April.

But as trendy as lifecasting may become, it will be just one of many applications for live video-streaming services, says Chris Yeh, Ustream's CEO and an investor and serial entrepreneur. Other customers are using Ustream to broadcast product launches, church services, college graduations, and the like. "I don't know for sure if [live video streaming] will be big, but it's one of those ideas that has the potential to be a multi-billion-dollar business," says Yeh.