Here a some YouTube links that Andy Mac sent me of kinetic sculptures by Theo Jansen. They are really worth a look as the mechanics of the sculptures are fascinating.

http://www.youtube.com/watch?v=a7Ny5BYc-Fs
http://www.youtube.com/watch?v=xdyb80yvjGE
http://www.youtube.com/watch?v=EK4Yg3kU4oE
http://www.youtube.com/watch?v=NulyDjjyGa4
http://www.youtube.com/watch?v=4ZK4V2YUA5U
http://www.youtube.com/watch?v=-GgOn66knqA