Rioform Loop Chair

Single sheet of folded up polypropylene from Rioform. The shape acts like a spring. They don't give a weight limit, but they do say it works fine with a 120kg (265lb) person. Another one of those stunning, simple ideas that makes me feel stupid for not thinking of it myself. Designed by Brazilian Jorge Lopes, and a bargain at $475.

Rioform carries a lot of interesting work from other Brazilian designers.