Izhar Gafni makes bicycles out of cardboard. The Israeli mechanical engineer can make a 20-pound bicycle that will support a rider of nearly 250 pounds, and its low-cost components make it unattractive to thieves — Gafni fashions the frame, wheels, handlebars, and saddle from sheets of cardboard that are folded and glued together; the tires and drive belt are recycled rubber, and the seat and some of the gears are made of recycled plastic bottles. “It’s one of the most green products you can imagine,” his partner Nimrod Elmish told the Times of Israel in 2012.

The company is pursuing partnerships to distribute cardboard bicycles and wheelchairs in Africa at little to no cost for the end user. “There is much to say about cardboard,” Elmish said. “This bicycle is the beginning of a materials revolution.”