i saw a program on discovery channel regarding the air car and its technology.
the program says this is a workable technology and some indian companies are also working on this technology. i heard even TATAs are too getting into it.
it is even said , it have a compressor which will compress the air and can be self sustaining. Car running of just air....
Air car ready for production : Yahoo! Green
this is one of links for details.
Guy any more info please share.