The Air Car uses compressed air to push its engine's pistons. It is anticipated that approximately 6000 Air Cars will be cruising the streets of India by 2008. If the manufacturers have no surprises up their exhaust pipes the car will be practical and reasonably priced. The CityCat model will clock out at 68 mph with a driving range of 125 miles.

http://green.yahoo.com/blog/ecogeek/66/air-car-ready-for-mass-production...