I’m sorry, that’s total snake oil. It belongs in the same category as perpetual motion machines (and in fact, if it *did* work, it would require breaking the same laws of physics).

Sure, if something could magically(*) break water into hydrogen and oxygen, recombining them would yield energy. Of course, the problem is break apart water *requires* a large amount of energy – the exact same energy you get from combining them. You never get energy for free, it has to come from somewhere.

*These devices *don’t* split water into hydrogen and oxygen; that would require *serious* energy inputs. That’s why hydrogen is a potentially useful fuel – it’s good for *storing* energy (high energy-per-weight, and you can take any energy and convert it into hydrogen). You still need a source of energy (power plant, wind, solar, gas, etc).

The only thing you can do with water (sometimes) to improve a gas engine is to put a fine spray of it into the intake (which is probably what these do). It will vaporize (not split into hydrogen and oxygen), and in doing so absorb some energy (heat). This can cool the intake charge, allowing the engine to take in more mass (of air and fuel), yielding slightly more *power*. So racers sometimes use water injection for power – but it doesn’t help efficiency.

Please, please pull or revise this post. This merely makes progressives look like fools, and undermines our attempts to convince voters that plans like McCain’s energy plan are foolish and short-sighted. And your disclaimer doesn’t stop us (and you) from looking like you endorse it.