Walking the dog on the moon

http://www.space.com/businesstechnology/090213-technovel-axel-rover.html

The new Axel rover is cool and was designed for use on the moon, not Mars. Styled like a yo-yo, and with just three actuators, it attaches to another robot and can then descend into craters, unlike other rovers. It can control its own wheels and trailing link. It can pick and choose its way down a slope, even turning in place if necessary. It does other stuff, too. Ain't science grand?