The Balancing Cube, ETH Zurich
This is allot of fun for all you science weenies out there. I can just image all the cool applications this could be tied to in the future.
The Balancing Cube can balance on any of its edges or corners. It owes this ability to six rotating mechanisms located on each inner face of the cube. When the mechanisms (simply called modules) are actuated, they exert forces on the cube and shift the center of gravity of the overall system. The modules communicate with each other and coordinate their motion to stabilize the system.
Visit the Institute for Dynamic Systems and Control for more information.