Interesting reading - looks like quite a few guys hold the same reservations I do about the system. I'll keep on the sceptic side of the fence until I see actual, scientific proof that their is some sort of catalytic reaction happening which makes the engine run more efficiently. On a positive note, water injection does in fact work in changing the 'apparent' octane rating of a fuel with turbocharged engines (petrol). With water injection you can run more boost and more ignition advance before detonation occurs, and there appears to be more happening in the combustion chamber than just purely the cooling affect of the water vapourising. To be honest, its not going to be too hard to make a good argument that the water for fuel thingy works, and what worries me is they have been around for quite some time and there is not one shred of evidence that they do anything at all. At least someone could have two cars exactly the same with two drivers and two routes, swap drivers, swap the device, repeat the test 10 times and there should be a statistical difference - but my heart seems to think that wont be the case or it would have been shown positive already. In this case no news is bad news I think...