Say Hello to the Solar Powered Airplane

You won't be flying in any of these bad boys any time soon, but "solar powered drones that can fly for days at a time" has a great ring to it, no?

[W]hen a propane shortage nearly ended his record-setting ride in 1999, he began dreaming of a way to fly day and night without fuel, an idea that has reached fruition in a featherweight solar airplane set for an initial voyage across the United States starting on Friday, weather permitting. His brainchild, the Solar Impulse, will not be the first sun-powered plane to fly; its chief distinction is its ability to go through the night.