Has anyone ever come up with an engine design that uses centrifugal force to compress the air/fuel mix? For example, having cylinders spin at a very high speed around a central axis, using centrifugal force to compress the gases with a piston, and then the force against the piston on the power stroke to push down against a crankshaft, said power being used to impart forward motion to the spinning cylinders. Power is then taken off of the housing that the cylinders are mounted to.
Hey, you asked for original ideas. You didn't say they had to be good ideas.
Then there is always the good old fashioned Tesla turbine. Has that ever been developed into a useful product?
Gas turbine does this nicely. Need real small one. Better materials may yet make these practical for cars.
There was a WWII radial aircraft engine where the cylinders rotated around a fixed shaft.