Audi's Skysphere concept takes inspiration from cars of the prewar era combined with the latest in modern technology for a look at the future of mobility. The classic long hood, short deck proportions with retractable fastback give the Skysphere visual impact without being overly derivative — but it's what's under the skin that impresses. A steer-by-wire system controls both the front and rear wheels, while two driving modes — Sport and GT — shorten or lengthen the wheelbase by up to 10 inches. This gives the driver a fast-reacting, short-wheelbase sports car or a comfortable, long-wheelbase grand tourer for cross-continental trips. An electric drivetrain makes 623 horsepower with a range of 300 miles.