NEW YORK (CNN/Money) - In the 1950s, they used to call them "dream cars." Now they call them "concept cars," reflecting the serious thinking behind cars that have two engines, the ability to rotate in place or wide-screen TVs instead of rear windows.

Not all concept cars are that nuts, of course. In some cases, what a car company calls a "concept vehicle," is something that is clearly planned for production but not yet ready in every detail. Most concepts fall somewhere between flights of wild imagination and those boring "coming soon" editions.

Often, buried somewhere beneath the insane gadgetry that no right-thinking car company would turn loose from its factories, is an underlying car that you might actually drive to work one day.

Sometimes those right-thinking car companies surprise you, though. Someday soon, rotating in place might be part of the standard new-car test drive.

We spoke with James Bell, publisher of IntelliChoice and Joseph Baker , North American sales analyst with automotive consultancy CSW, about the concept cars from last week's Detroit Auto Show. Our gallery features some of the vehicles they thought would have the biggest impact.

Bell and Barker also commented last week on the new production cars coming out of the Detroit and Los Angeles auto shows. For that story, click here.