Parking can be good and bad... Last time I went to an event at 12 Galaxies I had to park several blocks away.
For tonight I will probably just walk since I live close enough. BART stops just a few blocks away as well as several MUNI busses stop practically in front of the place (ok on the corner.) I believe you can catch the 14 Mission, the 49 Van Ness, and any other bus that runs along Mission street, plus there are the Sam Trans busses that go by, I think the 5 Templeton stops within a few blocks. You would have to check when the last BART leaves 24th st station, but the MUNI busses run pretty and some all through the night.