I've been interested in, and doing research on, Brown's Gas aka HHO, for some time, and it DOES have potential. Watch this news report on YouTube:
YouTube - Water Torch
This water-fueled cutting torch is on the market, and he has a car running exclusively on water in the report as well. The argument used about pumping water up to the top of a mountain is a version of the old principle that you can't get more energy out than you put in, but there is a catch. If the energy is already there, from nature, you can get more out. Wind generators are an example, so are A-Bombs. Onboard electrolysis can be used in this manner. The problem with these cheap kits and plans on the net is that they don't address several issues. One is corrosion on vehicle components, from the engine through the exhaust. Another is they don't have metered flow, by tapping into the throttle position sensor, etc.
