Researchers from Carnegie Mellon University developed Ballbot a robot that moves around on balancing on a sphere.
The tall and thin robot featuring the typical American non-humanoid looks has intelligent circuits to balance very stable on the rolling ball. The video where the robot gets push are impressive as Ballbot is not swinging back and forth it stays vertical but moves to counter the push.
The CMU researchers aim at developing a personal assistant robot for household use. They do not believe that leg or wheel equipped robots are ideal for household use. More details and video on the Ballbot project site. Via Discovery Channel.