I spend most of my time in the mission, so:

go to philz coffee at 24th and folsom

check out the kilowatt bar on 16th street (just east of valencia)

check out the noisebridge hackerspace (its somewhere between 18th and 21st on mission, i can't remember)

if you're around on sunday night, check out the dark room on mission st. for some hilarious overdubs for "bad movie night"

also, let me know when you're in the area and we can grab a brew (dave [at] thathigh [dot] com)