Using the same publicly available data that feeds into Google's General Transit Feed Specification, transit-obsessed YouTube user STLTransit has created a trippy time-lapse video showing the movement of every Muni bus, BART train and ferry boat over a typical 24-hour weekday.
The city map is blacked out here, but the contours of the Bay can be made out in dark blue. The white dots are your trusty Muni routes (personally, we're mesmerized by the little dot doing runs on the 108-Treasure Island line), BART lines show up in their appropriate colors, and the various ferry services show up in shades of pink, blue and red.
Starting at 4 a.m., the video shows the Owl busses tirelessly plodding around the city when the first BART runs come in from Fremont and Pittsburg. By 6 a.m., the ferries have already departed Sausalito and Tiburon and the whole thing starts to look an ant colony that suddenly found some cookie crumbs downtown in the Financial District. Strangely, we didn't notice any meltdowns at Market and Church.
Anyhow, there's a slick, jazzy soundtrack to go along with the whole thing ("Golden Gate" by Gazzara, appropriately enough). Observe: