A MAKE reader spotted this Mechanical spider site in the How What Why forums – “It has been a hobby for a number of years to develop a “bicycle” without wheels that could walk. It would move on legs and resemble a large insect. A linkage was developed that satisfied the design criteria and several small-scale prototypes were built that demonstrated the concept. Applications for the linkage go beyond human-powered machines. The links are connected by pivot joints and convert the rotating motion of the crank into the movement of a foot similar to that of an animal walking.” – Link.