Okay, so it's not a gadget, but we're really impressed by this fantastic Stone Golem suit that players of the Mordavia LARP in New Zealand put together on the cheap:
This Stone Golem was constructed using about 5 foam mattresses, over 50 sticks of hot melt glue, and 8 cans of grey and black spray paint. The foam is glued in large thick sheets (approx 20cm thick) to a fabric bodysuit, and the deep cracks are carved into the foam surface. The bodysuit has a zip up the back to allow the wearer to enter it, and the zip is concealed by abutting foam. The soles of the feet are made of corflute that has been sliced in half to expose corrugations that act as grip. The arms are about twice the length of the wearer's arms, and act as swinging weapons made entirely of soft foam. The golem took about 100 hours of work to construct, between 3 people. On its first appearance, the Stone Golem sent twenty bold adventurers into a hasty retreat without so much as touching them.
[via Boing Boing]