I had a day off on a Friday. I recently relocated from Seattle to Oakland and decided to walk along Market Street in downtown San Francisco on this beautiful day. At the Ferry Building, I had heard about a "salty pig parts sandwich shop" and ate my lunch there.
I was about to walk to the Embarcadero BART (subway station) when I realized I was at the Ferry Terminal, and why not take a more scenic, above water route?
I was pleasantly surprised to learn my Pre-paid Clipper transit card would be accepted on the ferry, so there was no need to purchase a ticket (though you could add more to your card, or buy a ticket at a desk near the front door.)
The ride was beautiful and you can sit at the top of the ferry, taking in the sun and the breeze. Booze is served on board as well (I didnt purchase any, but a starry-eyed, twenty-something couple did.) You can see all of SF and arrive at Jack London Sq in Oakland. A free shuttle will take you up Broadway. Do it!