*cough*
Fossil fuel should be fine if we can make it last us.... oh I don't know... 10 fold? *cough*
Ethanol CAN work, and it is only "inefficient" when compared to gasoline; naturally, this is going to be the argument for any pro-gasoline advocate. What does this matter is it can be made cheaper? Honestly. Put your brain in gear and think about this.
A downside of Ethanol is the temperature at which it burns. Running pure ethanol in an engine designed for gasoline
can be done.... except we run into heat issues. An engine must be designed to handle these temperatures in order to really be practical. Same goes for hydrogen.
But back to what I was saying, burn the vapor of the gasoline (produced by agitating the liquid) instead of atomizing it (like a perfume bottle does) and *bam* there's the efficiency!
Hydrogen is also a promising alternative, and many people I know, just here in the valley, have built their own hydrogen generators and have cars running BASICALLY off of water. No problems, aside from the heat at which hydrogen burns; hotter than ethanol in fact.