This video is amazing, it gives some rough numbers about a way to make hydrogen from water that uses 2/3 less energy. It's amazing work by MIT:
http://techtv.mit.edu/videos/273-tiny-bubbles#comment-fieldset
You've gotta see this, it uses cheap cobalt and cheaper phosphate in very small quantities. This makes SOLAR power viable as a source of a heating gas that wouldn't require a chimney because it only gives off water when burnt. It makes hydrogen cars possible, which will piss off the oil men who have pushed hydrogen cars because they thought they were economically impossible,, or that they would use coal, natural gas, or oil to make the hydrogen. Now you can make it with solar power and use 2/3 fewer solar panels than you would have used prior.
Since we moved to a fossil fuel addicted country, research on cracking water to get hydrogen and oxygen had all but halted. Now a couple of guys in a lab have done the "impossible".