The HHOPP engine by TR Nowry
Price: $0.99 USD. 6300 words.
Published on December 8, 2009. .
A way of building high displacement engines (internal combustion, stirling, and diesel) in incredibly small physical packages. With all other things considered equal, the HHOPP version of the same power and displacement engine will be 1/4 the size or smaller than conventional designs. Bonus--the Million ton flywheel