Tata Motors has unveiled the world's cheapest motor car at India's biggest car show in the capital, Delhi. The vehicle, called the Tata Nano, will sell for 100,000 rupees or $2,500 and enable those in developing countries to move to four wheels. The four-door five-seater car, which goes on sale later this year, has a 33bhp, 624cc, engine at the rear. It has no air conditioning, no electric windows and no power steering, but two deluxe models will be on offer.