In December San Francisco "completed a yearlong project to convert its entire array of diesel vehicles — from ambulances to street sweepers — to biodiesel, a clean-burning and renewable fuel that holds promise for helping to reduce greenhouse gases" according to this article. Virgin soy-based biodiesel, though (our DBI vision focuses more on non-food-crop-derived biofuels).
SF has also launched "SFGreasecycle, a free program in which the city will pick up used cooking oil and grease from local restaurants, hotels and other commercial food preparation establishments. Those substances then will be turned into biodiesel, a fuel made of plant oil that burns cleaner than petroleum-based fuels." (link) Hopefully this fuel will supplement or replace the virgin soy-based biodiesel.
Some good ideas for Valley municipalities here?
It's worth noting that SFGreasecycle has some skeptics.