What's this? A Mr. William H. Gates, III, (that would be Bill Gates of Microsoft fame, of course) is listed as one of the inventors on a recent patent application for an "Electromagnetic engine." What's that mean? According to the filing at the U.S. Patent and Trademark Office, the contraption somehow "converts mechanical energy of a piston to and from electrical energy during each piston cycle." There are two engine designs illustrated in the patent, and the basic premise of both is to combine the electrical generating capabilities of a generator with the moving pistons of an internal combustion engine.
Also on the patent filing is a design for a "plasma injector." Ostensibly a replacement for a spark plug, the plasma injector would kick off "a chemical reaction" (think: combustion cycle) that would be required to get the piston moving in the first place. It's all rather interesting stuff, and if you've got an hour or two (or ten) to digest it, click here
[Source: U.S. Patent and Trademark Office