h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

I think that circular saws are allowed, they just have to be basic steel, without ceramics or diamond tips etc, afterall dead metal has one. I remember this as one of the better robots was disqualified for having a ceramic circ. saw that shattered during the competition.

I could be wrong but...

another idea, what about a armoured hovercraft?! it could just lower itself to the ground to give it 'traction' during an attack, or use its weapons whilst being floaty light for a quick getaway. does anyone know of any attempts?