The Dublin art studio Robo Steel makes elaborate and totally kick-ass sculptures out of scrap metal. Here's their Predator sculpture made from "sheet metal, washers, chain, bicycle spokes and other bits of recycles steel." Over at Neatorama, we've previously featured an Alien sculpture that they made.
http://www.robosteel.com/sculptures/predator/predator-1-2m-carrying-alien-head.html via Great White Snark