Check out this nutty video of DARPA/Boeing's DiscRotor concept, a flying craft that combines the VTOL (vertical takeoff/landing) capabilities of a helicopter with the long-range capacity of an airplane. It starts off looking like a normal 'copter, but once it hits speed the rotors retract into a low-drag disc atop the machine; then forward momentum coupled with vertical propellors or turbines mean the conventional wings can keep it aloft. Pretty darn inventive.