"Each block can rotate 180 degrees around the link that connects it to its mate, and each module contains a magnet that can be switched on and off, enabling it to connect to other modules in the system. Genetic algorithms allow the robot to discover new ways of moving on its own."
Best lego kit ever.
Also, The OmniTread:
"The OmniTread is divided into five box-shaped segments connected through the middle by a long drive shaft spine that drives the tracks of all segments. Bellow s in the joints connecting the sections inflate or deflate to make the robot turn or lift the segments. The bellows provide enough torque for the OmniTread to lift the two front or rear segments to climb objects."(38MB WMV)