It is strange to me also, but if it is possible to use a misture of water elements and gasoline to improve your mpg by (lets say) 30%, then it would be a really good idea.
Sure, using a hybrid gas engine/fuel cell combo sounds like a great idea, but the energy for electrolysis would have to come from the engine, and you will always net out less energy then you put into the reaction. Compared to new hybrid ideas, like thermal hybrids, hydraulic hybrids, and even the conventional battery hybrids, this idea is foolish.
However, this "egas" engine that they talk about on that site is a complete crock. They may be able, as they claim, to hide from the military-industrial complex, and the oil industry with their "revolutionary" idea, but they cannot hide from the foundation principles of the universe. You cannot get more energy out of reaction than you put into it.
Think of it this way. You put water into a container. Then you pour it out of the container. There is, aside from factors we aren't considering, like rain, no way that more water appeared in the container. In fact, thanks to evaporation, there is probably LESS water in the container.
A chemical reaction, grossly simplified, is much like that. An amount of energy goes into the chemical in order to form the chemical bonds (in this case, to form H2O). When the bonds are broken, one cannot get more energy out of it than was stored initially. And that is not even what they're claiming... they're claiming that they can get energy out of COMBINING them back into water, in a plain cylinder...
True, as everyone has been saying, we can't explain everything. But I think that we can, until we see real, substantive proof, explain this - it is baloney.