I been watching a documentary on future Cars and fuel. There are several options Hydroden(H) produced using electrolysis, Compressed air cylinders (Running cars on comprssed air), Electric cars, Solar cars, Hybrid Biofuel cars running on ethenol and other substances. However the concept of Cars running on Air really made things look simple, It is a beautiful idea, simple and cost-effective. http://www.theaircar.com/ and http://news.bbc.co.uk/2/hi/africa/988265.stm It is really good and cheap.