This is an eight legged spider walker beam. It can avoid obstacles using an IR radar. It walks with help of 2 simple dc motor and a lot of gears. The "brain" is a PIC 16f84 microcontroller. The construction takes about 1-2 weeks and the cost is minimally (mine cost's less then 10$). 4 rechargeable battery are used as power suplie. More about here: http://193.226.19.131/~lkajcsa Email: laci@personal.ro