I think it was the Sunday Morning TV show that I was watching (my wife TiVo's it) where they spoke with Willie Nelson and his biodiesel doin's when I became confused. And I do recall reading (somewhere) something along the lines of, "biodiesel is the wave of the future." Wave? We're onto another wave? I barely understand regular diesel fuel (I guess I should say I understand diesel as well as regular gasoline which is... well, zero. "Fill 'er up" is about all I can claim to understand) and now I have to learn another fuel? So I looked around. Well, it turns out biodiesel is a fuel made not from old dinosaurs but from vegetable oil. Read this (from the so-so-so great Wikipedia):

Biodiesel is fuel made from renewable resources such as vegetable oils or animal fats. It is biodegradable and non-toxic, and has significantly fewer emissions than petroleum-based diesel (petro-diesel) when burned. Biodiesel functions in current diesel engines, and is a possible candidate to replace fossil fuels as the world's primary transport energy source.

Whoa! Why aren't we all using it now!? Oh, where do you get it from? That's the problem. You have to grow plants to make it and that takes clear land and lots of water. But those crazy scientists out there are coming with all sorts of ways to make a lot of biodiesel without a lot of land and/or water. So, it biodieselwill be the fuel of the future. And I bet it happens before fuel cells. See how cool Wikipedia is?