San Francisco, for all its gut-crushing hills, has a huge bike culture that you can be a part of even if you're only visiting. Check out these places for decent bike rentals or a cheap used bike (you can sell it back when you leave or donate it to a bike-oriented worthy cause). It's more fun to experience the city when you're actually out in it, rather than encased in the hermetically sealed splendor of a taxi or a rental car. </img>
