Single Piston Auto Engine

And more undergoing R & D:
http://money.cnn.com/2016/11/22/technology/israel-tech-cars-autos/index.html?iid=ob_homepage_tech_pool

That's cool! [suspension/shocks in wheel ~spokes~] so the rest of the vehicle can be much simpler. Not obvious that would "increase efficiency" though. Seems failure modes could be quite catastrophic? Tom