Are you sitting comfortably? Probably not. But don't worry. Richard Buckminster Fuller's Dymaxion car was one of those prototypes that never took off, even though its inventor hoped it might literally do just that.
It was living in inadequate housing and seeing his daughter die of pneumonia one Chicago winter that made "Bucky" determined to improve the human condition. Searching for a cheap, lightweight, stable form of shelter, he began studying the geometry of the universe, which he concluded was based on arrays of tetrahedra. Applying this theory to building design led to the "geodesic" dome and overnight fame.
But some of Bucky's other inventions are less well known. Among them was the energy-efficient Dymaxion house, the name being a contraction of "dynamic maximum tension". And then, in 1933, came the Dymaxion car. This streamlined 12-seater was about six metres long, yet so light that it could travel 30 miles at speed on just one gallon of petrol. It could also turn round in its own radius, thanks to a steerable rear wheel.
One day, when stronger alloys became available, Bucky intended that his eco-car would fly. But in the meantime, that little rear wheel was to be its undoing. It was said to make steering tricky and counter-intuitive, and when a demonstration for a British enthusiast resulted in a fatal collision with another car, the press turned on it. Even though the other driver was at fault, the papers called Bucky's invention a "freak car".
Orders for a Dymaxion car two were promptly cancelled and the project ran into the sand. A smaller five-seat version with front-wheel steering appeared in the 1940s but by then the damage had been done. Nothing but an upsurge of environmental awareness could save the eco-car from oblivion.
And that was decades away.