Over the past several decades, the promise of the "car of tomorrow" has remained unfulfilled, while the problems it was supposed to solve have only intensified. The average price of a gallon of gas is higher than at any time since the early 1980s. The Middle East seems more volatile than ever. And even climate skeptics are starting to admit that the carbon we´re pumping into the atmosphere might have disastrous consequences. To these circumstances, automakers have responded with a fleet of cars that averages 21 miles per gallon, about four miles per gallon worse than the Model T.