Automatically Hardening Body Armor

Deflexion, developed by Dow Corning, is a material that is normally soft. When something hits it, the material instantly hardens, and then returns to its previous flexibility. So far, it's being used to make body armor for athletes, such as motorcycle riders and rodeo competitors. Dow Corning says:

It can be stylishly incorporated into a garment such as a base layer shirt, it can be designed to create protective equipment, like a soccer shin guard, or it can be incorporated into protective cases for delicate equipment. Because this high performance fabric is flexible, it can be cut and sewn directly into clothing, eliminating the need to insert uncomfortable padding. It can be layered, so garments can be customized with increased levels of protection for specific areas.

Link via DVICE | Image: Dow Corning, Screenshot: Core77