Seeing something like this and immediately it smells like the oil-companies just pay people to keep their mouths shut about it so they can stay in business. Considering how effective that practice has been so far, and the yearly gains in profits, you can only imagine the money they're shelling out. Aside from the bitterness, two words come to mind: Freakin' AWESOME! As for the fact that the welding flame is only warm, is because of the amount of water in your body and virtually the only thing that heats up is the oil on your fingers.
YouTube - How to use Water as Fuel for your Car - Hydrogen HHO Car