...What are these? Something to do with hydrogen? Despite it not making sense for you to write it that way if you meant H2O, I really enjoy the silly idea of a water generator (as in, making water, not running off water).
HHO generators are a car mod that some backyard scientists got into, but didn't actually work. They involve cracking hydrogen from water, and making explosive gasses some claimed could make your car run faster. There's lots of YouTube videos of people playing around with them. Kinda dangerous seeming... Still neat.