Aluminum wire. A jig. A pair of pliers. A LOT of crossing and bending. Probably some band aids.
Designer Kouichi Okamoto of Kyouei Design created "The Composistion Chair" using only a pair of pliers and a jig to bend aluminum wire. No bolts, soldering, reinforcements, screws, nails, glue, or welding required.
Those kids in high school that used to make hand-wound chainmail got nothing on this chair.