Scientists have developed a way to make T-shirt fabric reinforced with boron carbide, which is the same material used to strengthen military tanks. Boron carbide has a hardness just short of diamonds. Imagine that strength in a regular lightweight shirt!
To turn cotton bulletproof, researchers from the University of South Carolina and their collaborators from China and Switzerland dipped sections of regular T-shirts (Fig 1a) in a special mix of nickel and borate. After allowing the cotton to absorb the mix for 2 hours (Fig 1b), the textile was dried quickly in an oven and cured at a high temperature for 3 hours. Once ready, the pieces of cotton were placed in a furnace and headed at 1160°C for 4 hours while continuously aerated with argon. Finally, the resulting fabric pieces (Fig 1c) were cooled and analyzed using electron microscopes and a barrage of strength tests.
So far, the performance of the material is not up to Kevlar standards, but with some tweaking, body armor may soon be as easy to wear as any other clothing. Link