Jody Gnant stops broadcasting when she steps in the shower or goes places that ban cameras. Other than that, her life is an open video feed.

Jody Gnant stops broadcasting when she steps in the shower or goes places that ban cameras. Other than that, her life is an open video feed.

Two months ago, the little-known singer and songwriter from Phoenix wanted to promote her sound, which she calls a cross between Janis Joplin and Jan Brady. So Gnant, 29, turned on her webcam and became a so-called lifecaster, streaming live video of her every move 24-7.

Her biceps are now so strong from carrying her webcam-equipped laptop that she bowls with a ball that's 2 pounds heavier. Her self-made reality show has drawn so much attention to her music career that she has sold nearly 1,000 CDs, and her music video is being featured on MySpace and in movie theaters.

"I no longer feel alone," she said. "I feel like I have people rooting for me every step of the way."

Call it Reality TV 2.0, the next step in the Internet's evolution as an entertainment medium.

Gnant and a growing number of people are turning cameras on themselves and on their worlds, broadcasting the results in real time.

Lifecasting is a natural platform for the millennial generation, used to living their lives in public, posting details of every hook-up and break-up on their Facebook or MySpace pages.

As with any new medium, people are trying to figure out the rules of etiquette. The phenomenon raises questions about the privacy of people who might not want to appear in the live streams, as well as copyright implications of, for example, broadcasting music that's playing in the background.

But companies such as Ustream in Los Angeles, which powers Gnant's webcast, and Justin.tv in San Francisco are racing to become the dominant purveyor of such live, unfiltered programs. In the past year, the technology behind live streaming has become so inexpensive that start-ups can afford to give it away in hopes that they can make money through the mainstays of TV's reality shows: advertising and product placements.

"It's pretty obvious to everyone that TV is migrating to the Web," said Paul Graham, a founding partner of Y Combinator, an investment fund backing Justin.tv. "This medium will create a bunch of new stars."

Justin.tv gained notice in March when co-founder and namesake Justin Kan, a 24-year-old Yale graduate, strapped a camera to his head and started streaming every moment of his life over the Internet. Thousands of people crowded chat rooms to tune into his irreverent, sometimes crude and completely uncensored life.

Viewers see the world through Kan's eyes — except when he goes to the bathroom (he points the camera toward the ceiling), has a romantic moment (he takes off the camera) or enters a confidential business meeting (he mutes it).

The Justin.tv crew has raised more money and refined the video-recording technology to make it lighter and more portable. Kan can now clip his tiny webcam anywhere.

The company plans to open its network to all would-be broadcasters, banking that lifecasting will siphon viewers from TV by bringing programming to the people.

Live video taps into the contemporary, free-wheeling zeitgeist, said Justin.tv Chief Executive Michael Seibel.

"You no longer need to imagine what it would be like to witness the protests in Myanmar, camp out at Burning Man or even spend a day in the life of an up-and-coming Parisian fashion designer," Seibel said.

For its part, Ustream already features a lineup of more than 48,000 broadcasters, including aspiring entertainers and even presidential hopefuls, who collectively produce 5,000 hours a day of programming.

These start-ups are the latest contenders in a "viral video revolution" that has attracted an enthusiastic following — and some envy — among traditional media executives who are eager to reach young people.

Some observers are skeptical that amateurs will be able to capitalize much on the trend. Forrester Research analyst James McQuivey said Internet reality shows were a novel social experiment that would generate flashes of brilliance and mountains of mediocrity. But he doesn't think most people's unscripted, unedited lives are compelling enough to woo advertisers or sustain viewer interest. "As a large-scale business, I don't see it," he said.

But the Web is giving birth to new stars. Justin.tv features Naked Cowboy, a Times Square busker who plays guitar for tourists in his underwear. The Ustream network features a group of actors producing a 10-part television series: "35."

Few people have the stamina to broadcast their entire lives. Instead, they showcase events such as weddings, baptisms, even funerals.

When her grandparents couldn't attend her graduation from Stanford University, 22-year-old Marie-Jo Mont-Reynaud used Ustream to let them watch the ceremony, plus a performance when she jumped onstage to dance with the Stanford band and try playing trombone.

"My grandma loved it," Mont-Reynaud said.

Some established entertainers are using live Web streams to boost their profiles. CW's teen television drama "One Tree Hill" is experimenting with live chats with cast members and plans to broadcast the filming of a scene on Justin.tv.

After playing a sold-out concert at New York's Gramercy Park one August evening, the three Jonas Brothers piled into a limo and headed to a record store in Times Square. Fans mobbed the teen rockers as they bought their new album, which Hollywood Records had just released.

Every second was captured on camera and shown live on JonasBrothers.tv, one of nearly 700 channels featured on Justin.tv. More than 110,000 people tuned in for at least part of the broadcast and chatted in online forums.

"It was really awesome to be there with all our fans and for everyone at home to be there with us, too," said Kevin Jonas, 19. "To have the capability of going straight to the fans and communicate with them is the best thing ever."