Michigan State University researchers presented a prototype propulsion system that could completely replace the internal combustion engine in vehicles. The design, called a shock wave generator, does away with the crankshafts, pistons and valves in favor of a rotating round disc with wavy grooves.
This prototype uses 60% of the fuel for motion, compared with standard engines which only use 15% of the fuel for motion. Add to this the fact that it would reduce the weight of vehicles by up to 20% by removing the transmission and cooling system and you get one hell of a fuel efficient vehicle.
To read a description about how this thing works, hit the break.