Four tech guys living in an apartment in downtown San Francisco have just launched Justin.tv, a site where you can watch the world through the lens of a camera strapped onto the helmet of one Justin Kan. Live. Twenty-four hours a day. Even when he’s taking a leak. Apparently until either you, or Justin, cease to exist.

Oh, and you can also chat about it in real time with others who are doing the same thing, or watch highlights of his life. Or you could call Justin directly. Go ahead! His number, posted on the site, is 415-948-3219.

Justin was formerly the founder of Kiko, a now defunct online calendaring company that he started two years ago and was funded by Paul Graham’s early stage fund, Y Combinator. They ended up selling the assets of the company for $258,000 on ebay, and now Paul’s back as the financier behind Justin.tv.

So, what’s it like watching Justin’s life? Well, he mostly goes around meeting with Silicon Valley entrepreneurs and other twenty-somethings hanging out in SF. A few days ago the cops showed up at his apartment in response to a prank caller claiming there was some bad sh*t going down. Oh, and there was the night when all his buddies tried to push some site to the top of digg. Not exactly HBO.

But the interesting thing here is that the guys behind Justin.tv are apparently using the web site to test out their technology and garner some publicity so that in the future, when they launch their *real* business, we’ll all be able to stream our lives to the world 24/7 wherever we may be. Think about how awesome that will be. Um… yeah.

Are these guys brilliant marketers? According to Alexa, Justin.tv has skyrocketed after only being live for seven days to a traffic rank of 3,086. Not bad, really. And the media is flocking…who wouldn’t want to write a story about these guys…inevitably it makes us all ask the question, “(Why) Would people want to watch my life 24 hours a day?”

Or is Justin.tv going to end like the story of the man who had his name legally changed to dotcomguy, and locked himself in his house in January 2000 for a year with a few dozen web cams and a laptop with an Internet connection, so all the world could watch him…um…shop online.

Dotcomguy also generated massive publicity, and was reportedly getting about 20 million page views a day on his site the first month he went live. But by the time he finally emerged from his house a year later and rode off on his moped, the sponsors funding his adventure had reneged on their commitments and dotcomguy had become a joke within the tech community.