San Francisco is one of the top vacation destinations for a reason - it's a beautiful place with tons of stuff to do.
Check out the
SF Weekly if you need ideas.
Siteseeing: The various Bay Cruises are fun (they go under the Golden Gate bridge, the Bay bridge and past Alcatraz - good photo ops and interesting histroy narrative)
If you are into art: The Museum of Moden Art is awesome (plus many other museums)
If you are into clubbing: Ruby Skye, 1015 Folsom (plus many others)
If you are into Italian food: North Beach (take your pick)
If you are into seafood: Fisherman's Wharf or Farallon (my favorite, near Union Square)
Strip Clubs, massage parlors, sex clubs, you name it - they don't call San Francisco "Baghdad by the Bay" for nothing...
Pretty hard to not have a good time here (as long as you avoid the seedier parts of town).
ADG Webmaster