It seems the future may belong to Hybrid Diesels:
http://www.evworld.com/article.cfm?storyid=493
"It's called the VW 2 Liter, which means it sips just 2 liters of fuel every 100 kilometers. That's about 117.53 miles per gallon in US terms.
I might be interested in autocrossing that car but a 1,500 pound doodle bug on the road is not my idea of feeling safe. If a 4,000 or 5,000 SUV or car hits that thing at anything over 30mph, you are seriously injured or dead. China is getting ready to bring those small death traps to the US.
Hyrid cars are more expensive and depreciate more rapidly. If the tax advantages were taken away, these things would not sell. Then there is the expense of replacing the batteries and no one talks about the env. impact of dumping millions of those dead batteries.
Recently an Air Force C5 flew coast to coast with a mixture of Aviation Gas and a mixture of natural gas and coal mixture. This derivative cost between $45 and $70 per barrel. This could be used in automobiles in the next few years.