The Cubli is a robotic cube 15 centimetres in length that can stand up, balance on one edge, balance (amazingly) on one corner, and move around with no assistance using gyroscopes.
Three ‘reaction wheels’ inside the cube spin and brake at precise intervals, based on data gathered by the cubes sensors, and produce angular velocity which allow the cube to do its mesmerizing maneuvers.
What the above really means is the Institute for Dynamic Systems and Control in Zurich have created a cube shaped robot that can walk, roll and balance with eerily precise movements, and appears to defy the laws of physics, making for an extremely cool proof of concept device.
Research is ongoing into using the technology to build self-assembling robots, and to aid in planetary exploration.