Tiburon Ferry is ran by the Blue & Gold Fleet and connects Tiburon to the rest of the Bay. It takes about 25 minutes to get to San Francisco.

There's a commuter service during peek hours and during regular hours is mostly frequented by tourists.

It's a great way to see the Bay and you'll enjoy great views. They have a bar on board. 

http://www.blueandgoldfleet.com/tiburon-ferry/