I've recently discovered some interesting videos on youtube demonstrating the use of water as a fuel. In one case, salt water is placed within a radio frequency generator which produces an incredible flame.

Burning Salt Water:

http://www.youtube.com/watch?v=h6vSxR6UKFM

And in another case, a company has developed a unique technique of electrolysis for producing HHO gas on demand.

Water Fuel:

http://www.youtube.com/watch?v=vm5JhpWt4GQ

With hydrogen being the most abundant substance in the universe and the fuel of the stars, it would seem to make sense that it is just a matter of time until we're using it as our primary energy.