I'm not sure if this is cliche, but I saw this on television once and thought it deserved a physics-rundown (It was a future weapons episode).
This bulletproof vest, called "Dragon Skin," is manufactured by Pinnacle Armor. It was designed for military use, though it failed Army inspection (the heat test: the vest was heated up to 170 degrees F and was shot at afterward. The clay material backing couldn't withstand the heat, and the design lost its overlapping shape. The integrity of the vest was lost, thus the vest was deemed unsafe). HOWEVER, despite this subtle detail, the vest's design is truely ingenious.
The overlapping-disk design distributes the impact of a bullet to multiple plates, whereas on a single plated vest the force is absorbed by only one plate. On the specific epistode of Future weapons where this armor is featured, it withstood a number of tests, including shots from an AK-47 and an M67 grenade. In the case of the grenade, even though the vest itself was ripped to shreds, the armor itself was still intact.
The vest was officially declared to provide "level 3 protection," which means that it can protect agains 9.6 g bullets traveling at 847 m/s, give or take a few m/s.
...For those of you with an interest in physics and no occupation to apply it to, the military is looking for creativity