One of my favorite documentaries--and one that suckered me into making films myself--is Agnes Varda's 2000 masterpiece, The Gleaners And I. [it's $27 at amazon.]
It turns out that there's an obscure gleaning law on the books in Los Angeles, and harvesting fruit that hangs over public property--like streets and sidewalks--is perfectly legal. There's a website called Fallen Fruit that puts together neighborhood maps for anyone who wants to get to picking. [via boingboing]