Except that it's a car, developed jointly by scientists at Cranfield University with Lotus Engineering, Volvo and Alcan, the giant aluminium producer. Together, they developed a five-door hatchback which weighs just 600 kilograms - about a third less than standard cars - and can manage up to 140 miles per gallon while having a top speed of 180kph (110mph). That is almost five times more than the average car manages in the city today - which for short, stop-start journeys, would make this very cheap to run.
Reaching that weight involved taking out heavy items such as power steering and brakes - but that meant that the car was lighter, so they weren't needed. "It's a virtuous circle," says Kenneth Sears of Lotus Engineering. "Because it's light, you don't need a heavy engine. Then you have an even lighter car. So you can have an even smaller engine. And so on."
The breakthrough car, which is among the designs on show later this week in a new exhibition, "The Car, Your Future?" at the Science Museum in South Kensington, London, took just a year to design. Now, the developers aim to build a prototype and have it running by 1999.
But some of those on the project - such as Dr Steven Cousins at Cranfield - think it is also time for the Government and manufacturers to embrace the challenge of mass-producing a car that would drastically cut outputs of greenhouse gases and smog, and conserve fossil fuels.
"We're convinced, from our own market research, that there's a market for this car," says Dr Cousins. "It would cost about pounds 7,000 in mass production and it would be exciting, but with high economy."
He suggests that the Government could also give a lead to vehicle makers. "If cars that can do more than 100mpg didn't have to pay road tax, I think that the industry would supply them," he says. "I think tax breaks would be very useful there."