I'm a forager. In the summer, I can eat my daily serving of fruit by walking Berkeley's streets. I've exchanged my garden herbs for fruit via Forage Oakland.
In my neighborhood, the fruits of the strawberry trees (Arbutus unedo) are ripening. Verifying the edible nature of the fruit, I discovered a blog entry at Algarve Buzz about Aguardente de Medronho, a Portuguese wine made from the fruit.
Another common urban plant is the dandelion. I have yet to forage the dandelion because of its growing sites - sidewalk planting strips where dogs often urinate. Did you know that wine can be brewed from dandelion?! Felicity at Thrifty Living writes about the process here.