We at AutoblogGreen have a whole section devoted to hydrogen. Besides for fuel cells, hydrogen is notable for being lighter than air, so it floats. There are, of course, other gases which float, such as helium. Helium is also noted for making your voice sound like a cartoon character, but that's neither here nor there. Back to being lighter than air; people have been using helium balloons to launch themselves into the air ever since Larry Walters did the deed back in '82, which sparked an entire episode of Mythbusters trying to duplicate the stunt with weather balloons, and succeeding! So, Kent Couch strapped 105 balloons to a lawn chair, packed some goodies with him and took off for the sky. Nine hours later, he landed, 193 miles away from where he took off. Obviously, there are other ways to travel 200 miles in nine hours, but most of them involve burning fossil fuels! Not good old Kent Couch, though. No fossil fuels were harmed for the entire duration of the trip.
"When you're a little kid and you're holding a helium balloon, it has to cross your mind," he says. Yeah, but most of lack one critical aspect: guts. Perhaps we just have a greater will to live. I guess it all depends on your perspective. We are certainly not condoning this activity, as it is still illegal unless you somehow get permission from the FAA. Good luck with that.