Photo: Eric Long / Smithsonian National Air and Space Museum
It goes without saying that the Smithsonian National Air and Space Museum has some of the neatest collection of planes in the world, but this one is particularly intriguing: fly-powered aircrafts built by famed aircraft modelered Frank Ehling in the 1970s.
The AirSpace Blog has more:
Designed and built by famed aircraft modeler Frank Ehling in the 1970s, they are the smallest flying models the Museum owns. But more unusual than their size is that they are powered by flies – yes, you heard right, houseflies, the insect. Constructed from balsa wood and red tissue paper, the one-fly design has a wingspan of two inches, and the two-fly version, which features a delta-wing design, is four inches wide. In both cases, contact cement was used to attach the live powerplant to the fuselage.
Link
If you're skeptical, there's a video clip of another fly-powered airplane, this time by inventor Thomas Fetterman (oh, you can also buy the kit from his website)