[kach22i]

Boeing putting fuel cells in an airplane
Boeing doesn't think fuel-cell technology will ever power commercial aircraft, but the company does think it has the potential to power smaller airplanes and unmanned craft........................................ with no internal combustion engine of any kind involved.


Better article here:
http://blog.wired.com/defense/2007/03/engineers_have_.html
The demonstrator aircraft is a Dimona motor glider, built by Diamond Aircraft Industries of Austria, which also performed major structural modifications to the aircraft.


Note: There are some other cool things at that Sci-Fi site.