Volleyball
 
I used to play recreational volleyball. Here's some information about the adult volleyball leagues in the Bay Area. City Beach is a local volleyball club with various locations around the bay. The Industrial Volleyball Leaugue (IVL) is one of the leaugues I play in regularly.
 
If you have the QuickTime plugin installed with your browser, take a look at an indoor QuickTime VR volleyball court or an outdoor sand volleyball court.