"Developed by Genepax in Japan, this commuter vehicle is able to travel at 80km/h for one hour on just a single liter [approx. quarter of a gallon] of water. The concept is much the same as other fuel cell vehicles, except you don't need to feed the car with straight hydrogen. The Water Energy System (WES) and Membrane Electrode Assembly (MEA) are used to separate the hydrogen from the oxygen in water. Details are slim by they say this is accomplished through some sort of chemical reaction.
Genepax is currently shopping around its technology to various automakers, so we're not sure when (and if) these water-powered cars will ever make it into production."
via mobile mag