Audi, with the R8, has made a small rear-engined supercar. BMW's response to that could be the M10.

A great inspiration for the design of the M10 was the BMW E9 3.0 CSL, a great BWM sportscar from 1973.

Lot of it's design features are in the M10's design. The typical BMW 2-part-front grille is stretched vertically instead of horizontally like in modern BMW cars. The 4 round headlights are also integrated in the design, and the thickening of the bodywork around the rear wheels too.

Though, the M10 contains modern BMW design clues aswell, shown on BMW's concept car CS. For example, the overall shaping of the head- and taillights, the air intakes in the front bumper.

About the engine used there are more rumors. Some says that will be the V10 engine from the M5/M6, which will carry approximately 550 HP out in the M10. Another possibility is also the 4.0 liters V8 engine used in the M3.

Another options will be a V12 derivative of the current V10 used in the M5 and M6. The possibility exists, however, that it will merely get a blown version of that same V-10 engine. Either way, the car is expected to be a rear wheel drive two door, with power substantially more than 500 hp.

Since the M10 is rear-engined it will need some air intakes at the rear end of the car too. Two are placed on either side in front of the rear wheels, and two are under the taillights, with the shape inspired by the front intakes.