Quick, name a car with three-wheel drive. Okay, trick question; this isn't quite a car, but Peugeot's idea of a fuel-efficient all-weather runabout. The HYmotion3 Compressor Concept foresees a hybrid vehicle in more ways than one: part gasoline-, part electric-powered; part car, part scooter. The French automaker says it offers the stability of a trike with the protection of a safety cell similar to that which supports occupants of a Smart car.

One of the first things Eric Mattessich discovered in engineering school was that the typical internal combustion engine blows about 70 percent of the energy it creates straight out of the tailpipe in the form of heat. So, he wondered, could he adapt the kind of heat-recapturing mechanisms used to make powerplants more efficient to work on hybrid cars? “The technology has been around since the 1900s,” he points out. “It’s just that no one has put it into such a small package before.”

Your car is going to drive you to work someday. Until then, car makers are experimenting with ideas that take control away from you in subtle, helpful ways – mostly to help increase fuel efficiency.