SF Events & Activities
Thurs 6-10 PM Nightlife at Academy of Sciences (discounted admission, 21+)
Mondays 8-11 PM Classical Revolution SF (Chamber Music) at The Revolution Cafe (3248 22nd Street @ Mission)
Third Wednesday each month: Nerd Nite
Throughout the week: volunteer with the Golden Gate National Parks Conservancy (planting native plants, maintaining trails, etc.), and lots of other events
Fun Cheap SF - a great list of stuff that, like the name suggests, is fun & cheap
Hidden SF's Best SF Events - great list of both evergreen (weekly) events as well as more ephemeral stuff
Yelp's SF Events Listing - one of the most comprehensive lists
SF Gate Events - created by the SF Chronicle
Bay Area on the Cheap - lists special deals, including various events
The Perfect Spot SF - good blog that includes upcoming events
KCSM Jazz Calendar - a comprehensive listing of Jazz events and concerts in the Bay Area
Love to Eat and Travel - includes non-SF information but is still interesting
Old Events (often repeat year to year)
ThinkWalks ("Nerdy Tours for San Franciscans")
California Commonwealth Club Events - lecture series on various topics, including many famous politicians and writers.
Omnivore Books on Food - hosts various food-related authors, in Mission district at 3885a Cesar Chavez St.
www.improv.org (BATS) shows most weekends
Other Fun Stuff
Stairway Walks - Having so many hills, San Francisco offers excellent "urban hiking" on stairways, which allow you to see some great views and discover hidden pockets of neighborhoods. The main resource is Adah Bakalinsky's excellent book, Sisterbetty.org has several stair walks posted online as well, along with photos.