Fleet Fox! An animated paper model for every one to print out and make for free. You can download the parts and instruction for this model at the Brother website here:
The model is powered using a crank slider mechanism. As the crank is turned the push rod/slider is moved up and down moving the fox. The legs are attached by paper straps to the top of the box lifting tem up and down as the fox moves.
Turn the handle and watch the fox run!