I llove watching Dirty Jobs with Mike Rowe on discovery. Many of the things he covers are alternative fuels, whether it is biodiesel or Methane Farms. Most of these things require something called Biomass--usually in the form of some kind of poo or discarded food.
Since at the basic point all you really need is something organic, I have a few ideas we could implement to create easily replacable biomass.
Pests: Flies, roaches, rats, mice, opossum, and groundhogs. No use for them, and there are always too many.
All forms of mushrooms. (If you eat them, know this: your average mass-produced shroom, the kind you get on a pizza, are grown in caves, and literally fed on horseshit. Not as a fertilizer, but as their sole source of food. Ick.
Any politician from Massachusets.
And anyone or anything from Uruguay.