FoundersDenJonathan Abrams ignited the social networking craze by making it easy for people to connect with groups of acquaintances on Friendster, the first successful social networking Web site launched in 2002.

But for his new project, a shared-work space/private hangout for up-and-coming Web startups and entrepreneurs in San Francisco, Abrams has made it so that not just anyone can join the club.

“We want to be very selective. We’re choosing companies that we think are cool and people we think are cool,” Abrams said of the project. “Because if you’re an asshole, or if you just want to sit in your corner and never talk to anybody, what’s the point of coming into a shared space and being part of a community?”

Dubbed the Founders Den, the 8,500-square foot office space in the city’s South of Market district is a place where entrepreneurs can set-up shop and code away during the day, and pour a drink from the bar and sidle up to the poker table at night, or drop-in on one of the many events to be held in the lounge area.

The space, which officially opens this week, can accommodate between 10 and 15 startups, with rents leased out in six-month increments. The idea is that startups will move into the space after receiving a bit of angel funding, and move out after they land their first Series A round of financing and begin hiring a larger staff.