There are a number of interesting bike designs made from a variety of materials, but one factor always held true: they're not generally made of cardboard. Well, designer Giora Kariv wasn't having that, so he went ahead and built a bike out of cardboard for $9.
Kariv brought his idea to a number of different engineers, all of whom told him that it was impossible. He did it anyway and managed to make a working bicycle that can hold a person of up to about 308 pounds.
Oh yeah, and it cost him $9.
He folded the cardboard like origami for strength and added a coating to defend it from the elements.
Though it might seem unlikely, Kariv thinks the bikes can be sold in stores for about $60. If so, they can be modified in a number of different ways, such as adding a electric motor.
Take a look at the video below to see Kariv explain the bike in detail.