Liora's comment: If dung from cows can be turned into biofuel, why can't we use human waste for the same thing? And add to that all the waste from our pets and other livestock!  Sounds gross, I know, but with 6 billion + people on the planet, and god-knows-how-many domesticated animals, "poop" is a resource that will never run out!

Put a Turkey in Your Tank
Biofuels from odd sources gain new fans

Changing World Technologies' refinery uses the feathers, bones, fat, and other bits from a nearby turkey-processing plant to make up to 500 barrels daily of bird diesel, which it sells to a nearby industrial facility. CEO Brian Appel says turkey oil is competitive with petroleum, thanks to recent U.S. tax incentives for renewables. U.K.-based Green Fuels makes machines that turn used restaurant fryer oil into biodiesel, and business is booming. A Danish company plans to convert thrown-out coconut meat into fuel for farm tractors. Folks in India are mixing dung and water in backyard "digester" boxes to produce biogas for cooking. Oil may be growing scarcer, says one consultant at New Delhi's Ministry of Nonconventional Energy Sources, but "dung is always available." True dat.