From New Scientist we have this interesting tidbit about a possible diesel fuel replacement... Jojoba oil. No, I didn't know what it was either.
Turns out it's a desert plant whose nuts (ouch!) can yeild half their weight in oil. This oil, more commonly used in cosmetics of all things, apparently is stable at very hight tempratures and gives off a lot of energy when burned. We are America. Our cars run on skin cream. Fear us.