We've gone a long way from the stiff, full-plate armors of medieval times. These days, we have body armor you can stuff down your shirt, and you're good to go for a firefight. Well, not really. See, despite what Hollywood has shown us, under-the-shirt bullet-proof vests don't really protect you that well. It'll do for a 9mm bullet, but for rifle rounds? You need armor that has ceramic plating, which not only restricts movement, it's fragile too.
Dow Corning may have a replacement that addresses those very issues with modern-day flak jackets. They've created a silicone-based textile called Deflexion. While its passive state is quite flexible, it immediately hardens upon receiving an impact. This rigid state diffuses the shock throughout the rest of the material. It then returns to its flexible, machine-washable state like nothing happened.
Deflexion's schizophrenic nature makes it perfect for body armor; in fact, rodeo bull riders and motorcyclists have already experienced the benefit of wearing armor made from the super textile. It would even make a great lining for a laptop case. You never know when you'd need to keep your portable safe from stray gunfire, after all.