I really like this idea: Village Harvest is a small nonprofit suburban harvesting cooperative in Santa Clara Valley, California. They fight hunger by turning a waste -- unused backyard fruit -- into a resource:

A backyard fruit tree usually produces far more fruit than a household can use themselves, and there is more than enough going to waste from our own backyards and farms to provide for our local community’s hungry. Village Harvest addresses this food distribution problem by organizing volunteer teams to harvest backyard fruit and donate it to charitable food agencies and organizations, by educating homeowners on fruit tree care and harvesting, and by providing education on food preservation such as making jams and preserves from home-grown fruit.

Last year, Village Harvest saved 81,441 lbs of fruit. (Thanks to Joe Deely for the suggestion!)