With a mission statement of "give the people what they want", Public Works defies self-identity :)
Founded by the Mighty folks and hosting everything from tech-events and civic projects/volunteering to art galleries and all-night-dance-parties, PW can be a worth a look.
For an intro to the surrounding area (the Mission!), and beyond, watch author Kevin Collins 2011 20-slides-in-5-minutes Ignite presentation at PW.
Address: 161 Erie St, SF
Website: publicsf.com