Perpetual Walking Robot is Powered by its Own Weight

Via: Gajitz
 This innocuous-looking robot has no power source, no “brain,” and no sensors of any kind. Yet it is a revolutionary piece of technology thanks to its unique method of locomotion: it basically falls and catches itself over and over. As long as it moves downhill, it can use its potential energy to keep moving indefinitely.
 Developed by the Sano Lab at the Nagoya Institute of Technology, this passive walking robot only needs a push from a human hand to start walking. In 2010 it walked a continuous 15 km over 13 hours, setting a new record in the Guinness Book of Records.
Human Hunting Robots?