Researchers at MIT and in France developed a new self-assembling polymer material with a structure like a layer cake. Resilient rubber layers alternate with rigid glass layers to provide durability and strength. To test its mettle, the team developed a way to shoot tiny microballs at the structure to see how it held up. When shot edge-on, like in the image above, the material warped and caved at the point of impact. When shot head-on, it was 30 percent more effective at blocking the speeding ball. The microballs were hundreds of times larger than the nano-layers in the armor, so they were a realistic simulation of a bullet impact.