I am also very interested in this subject and have been for some time now.
Have you ever heard of Stanly Meyer? Apparently he came up with a on board hydrogen generator that he installed on a dune buggy that run only on hydrogen!
The buggy didn't have a fuel tank but it had a water tank, plus according to him you can use water from a garden hose or salt water or ice in fact while I am typing this I will see if I can find the video's that I've seen to show you.
Ok it wont allow me to right now since I don't have many posts on here but just Youtube Stanly Meyer.
And after he told the world about it saying "he wanted to stop the oil embargo" he was dead soon after.
I feel he was definitely onto something.