Theo Jansen is a physicist student-turned-artist who makes large walking kinetic sculptures called Strandbeest, like this:
https://www.youtube.com/watch?v=KsqlnGMzMD4
This walking motion can be applied to bicycles:
https://s3-us-west-1.amazonaws.com/h...ng_bicycle.gif
A video of a bicycle with wheels walking:
https://www.youtube.com/watch?v=d3ukbYC9dZ4
Homemade drill-powered walking machine:
https://www.youtube.com/watch?v=mGOled86Sjo