I was playing trivial pursuit this weekend and I got this question… I didn’t believe it so I had to look it up on Wikipedia.
The Dymaxion car was a concept car built in 1933 and designed by Buckminster Fuller. The car was a high efficiency vehicle with a then-unheard of fuel efficiency of 30 miles per US gallon (7.8 L/100 km) and it could move 11 passengers along at 120 miles per hour (193 km/h).

The car was exceptionally large, 20 feet (6 metres) in length, but could do a U-turn in its own length. This turning ability was due to the fact that it turned via a single rear wheel. Drive power was provided by the front wheels, which were mounted on a 1933 Ford roadster rear wheel axle, flipped over to provide proper rotation. Henry Ford had given Buckminster Fuller the V-8 engine to experiment with.

The body was aerodynamically, if counter-intuitively, correct. It was blunt and smooth at the front, narrowing to a low-turbulent tail at the back. Still today, the intuitive “knife-edge front/matron-butt” fashion trumps aereodynamics at anything less that three meters above the ground.

This configuration unfortunately made the car somewhat counterintuitive to operate, especially in crosswind situations. The unusual steering ultimately led to the invention’s demise when an accident at the 1933 Chicago world’s fair, likely caused by the driver of another vehicle, prompted investors to abandon the project, blaming the accident on deficiencies in the vehicle’s unusual steering.

However, according to Art Kleiner in his book The Age of Heretics, the real reason why Chrysler refused to produce the car was because the bankers threatened to recall their loans as they felt the car would destroy sales for both vehicles already in the distribution channels and second-hand cars.