Microsoft founder Bill Gates appears as a principal applicant on a patent published last week by the U.S. Patent and Trademark Office, but the concept in question isn't computer-based; it's an electromagnetic combusion engine. The patent appears in the name of a Delaware-based LLC named "Searete," a purported shell company for joint-patent filings.

While the summary of the mechanism doesn't lend much insight into just how an engine like this would work in an actual vehicle, it goes into a detailed description of how the engine itself would generate power. The engine "... may be configured to convert mechanical energy of the first piston to electrical energy during a power stroke, and to drive the first piston" in the non-power strokes (ie, when the piston is intaking air or expelling exhaust.) In other words, the pistons can be moved by either gas combusion or by electricity.

It works like this: an engine's mechanical force, created by traditional combustion, could be converted into electrical or electromagnetic energy--which, in turn, could be used to help drive the pistons or for some other application. The benefit: an hybrid engine without the need for two discrete drivetrains, as with today's hybrids.

As the patent filing sees it, the application of an all-in-one engine like this could be much more adaptive that today's hybrids. In the patent's words: "... the engine may select between the first and second modes," that is, electric and gas-powered, "in response to actual or predicted operating conditions."

To be sure, this wouldn't look like your tradition engine; the patent stipulates that each cylinder will be non-circular and non-linear, meaning that an oddly-shaped piston will be traveling in an arc path through the engine, driving a helical gear box and working in concert with a battery source and a series of powerful electromagnets. For more details, check out the summary here.