Fuel Cell Flyer

http://www.strategypage.com/htmw/htairfo/articles/20091208.aspx

December 8, 2009: The U.S. Navy has been experimenting with powering
lightweight UAVs with fuel cells. One of these aircraft recently
stayed aloft for 26 hours. The Ion Tiger UAV is a 37 pound aircraft
that carries a 9.5 pound tank of compressed hydrogen to power the fuel
cell battery that runs the engine. Also carried is a five pound sensor
payload (day/night vidcam).