The Golden Gate Bridge. Alcatraz. Fisherman's Wharf.

Add Craigslist to your list of San Francisco landmarks, even if it is a virtual one. The site has become so synonymous with the City by the Bay, it stands to reason someone would make a movie about it.

Tonight on "Tech Live," we'll introduce you to Michael Ferris Gibson, who set out to make a documentary about the popular website on which people search for everything from jobs, apartments, parking spots, used cars, and event tickets to tennis buddies and romantic partners. We'll show you clips from his film, "24 Hours on Craigslist," a film as quirky as the people who've helped Craigslist evolve into the be-all, end-all of online bulletin boards.

Craigslist 101

Gibson describes the film on his website as "One day. One City. One website. No limits." The same words could be used to describe the site itself, which people not only use as an online classifieds section, but as a venue for venting on everything from the the war in Iraq to cheating spouses.

If you live in the San Francisco Bay area, chances are you've used the popular community website, which has been going strong since it was started by Craig Newmark in the mid-1990s.

Enter Gibson, and his quest to capture a day in the life of the site and the people who make it what it is. Capturing a snapshot of the site wouldn't be easy. Some 30,000 new posts appear on the now-international site every day.

People-powered passion

The first step in putting faces and personalities to the many posts on the site was getting a thumbs-up from the site's founder.

"His idea sounded great," Newmark said. "He was really respectful of the privacy of people who post on Craigslist, and he's really respected in the local film community."

For his part, Newmark is respected in the local Bay Area technology community. He's seen as a groundbreaking innovator who used the Web to channel information to the people who needed it most -- those in the community. He also chose to run Craigslist ad-free, a move that won him admiration from local Netizens.

Craigslist casting call

To find subjects for the film, Gibson did what any other Craigslist user would've done: He placed ads on Craigslist looking for folks who wouldn't mind being interviewed. Even the film's crew was recruited through the site.

"Well, the first day, which was August 4, was a forty-hour day for me -- a very long day," Gibson recalls of the first day of shooting. "Basically, in a nutshell, it was insane."

The response to his casting call was about as insane as his day was shaping up to become. About 1,900 people responded to his search for cast members. Though the crew didn't film everyone that day, it did decide which people's stories to tell.

The film works like the site itself, taking viewers through the process of selecting a topic and meeting the people behind particular postings.

The range of responses to Gibson's casting call was vast.

"We had people from Santa Cruz having a sex party," Gibson said, "and people up in Marin -- a red-headed family trying to find a new puppy dog for their little girl."

And then there was Mark Sergeant, who channels the spirit of Ethel Merman singing rock classics.

"He was looking for a band on our day," Gibson said of Sergeant. "He's a brilliant and amazing singer -- his story made a sort of [piece of] art for us."

Art imitates life

That artistic story is exactly why Gibson decided to make the film. He sees Craigslist as a melting pot of human expression.

"Making this movie is almost like making a movie about plumbing. [Craigslist] is just going to become something that people just use all the time," Gibson said.

In short, the film is a definitive social commentary about what Craigslist is about: San Francisco-area society.

With the film now shot, Gibson says he's looking forward to showing it at upcoming film festivals. If the popularity of the website is any indicator, "24 Hours on Craigslist" should be a huge hit.