yes. electrolysis, providing hydrogen either for injection to mix with gasoline or H2 combustion alone. Not a hoax at all, but highly misleading. 100 miles on four ounces of water...and how much gasoline was the H2 mixed with?
Like Leah said, electrolysis of water is energy-negative at the end of the day- whatever provides the electricity to split the H20 has to be replenished after driving- my guess is a load of batteries provides the energy to do it. Sure he can drive all day on water, but then he's gotta recharge them batteries! There's the rub.
As for the "HHO" gas, that's been sort of mysteriously claimed for a few dceades by several folks as being not-quite-a-water-molecule. This stuff is a bit like palladium in cold fusion- real enough of a material, but of dubious value in the way he claims.
Money-wise, it can still work at the personal level- water and wallsocket electricity is far cheaper than gas. But he sure isn't helping GHG emissions by using more juice from the powerplant. Unless he happens to have a PV or wind farm...
As for the torch, they've been around forever, including the onboard H2 generator. Not too effective for all but basic brazing or sweating pipe. H2 burns very clean (clear to pink-blue flame) and cool and the torch looks to be set up so all combustion is well away from the tip (no venturis in the nozzle). So the torch tip doesn't get very hot.
due diligence, following the links:
http://www.peakoil.com/fortopic10778.html
"Klein also has outfitted a 1994 Ford Escort station wagon with a smaller electrolyzer that injects his HHO into the gasoline in the car's engine. He said he has increased his mileage per gallon by 30 percent.
http://www.zpenergy.com/modules.php?...ticle&sid=1889
I suspect (but don't know) that, like acetone or high-octane fuel claims, the H2 acts as a sort of detergent in the cylinder, cleaning it- which can give impressive FE gains if one starts with a gunked engine initially. 5% or so I would buy on its own, but if he has data showing 30%, that is likely from cleaning the engine.