[Gravy]

I've seen a Geo gone full water get 95 mpg. And, that's full water, out of the tap and a dual re-use system. The guy filtered the water coming from the tank, released it in small amounts into the engine, just enough to run it, and after the burn efect, he ran it through another filter. He had horrible backpresure, but he re-used the water that didn't burn and re-cycled it into the tank.

I'm not sure where the link is, but for 100 mpg i'd be willing to drop a few hundred bucks.