Now this is pretty cool:

Army scientists are working on a liquid body armor for clothing that stays flexible during normal use but can harden to stop a projectile when hit suddenly.

Researchers hope the liquid could be used in sleeves and pants, areas not protected by ballistic vests because they must stay flexible.

The liquid, hard particles suspended in a fluid, is soaked into layers of Kevlar, which holds it in place. Scientists recently had an archer shoot arrows at it to see how well the liquid boosted the strength of a Kevlar vest.

"Instead of the arrow going through the Kevlar, it is completely stopped by the Kevlar vest -- and sometimes just bounces right off," said Norman Wagner, a University of Delaware chemical engineering professor who is working on the project.

Vests treated with the liquid have also blocked stabs from an ice pick, and researchers are doing more tests to see if it can stop bullets or shrapnel, too.

The uses for this are limitless. God bless American ingenuity.