The X-37B OTV has landed. (previously) and (previously) Launched in late April the space plane was tracked by amateur astronomers and sky watchers during its 7-month stay in orbit. The X-37 has he capability to maneuver changing orbit, track, and altitude. This led to a cat and mouse game with the earthbound skygazers. The X-37B is one of the latest in a series of experimental aircraft known as the X-planes. [more inside]
The ring wing or annular airfoil is an aircraft design which has been experimented with throughout the history of aviation with some interesting variations. It has served as the inspiration for several paper airplane designs, model airplanes of course, and a variety of children's toys. The capabilities imagined by the French coléoptère engineers of the 1950's and 1960's and the U.S. "flying tank" designers are available today at least in the form of unmanned vehicles (large PDF brochure, 6 minute video download, 1½ minute YT news clip). The technology has also been adapted to become the surfboard tunnel fin and there are underwater UAVs as well.