Medgadget is reporting that UCLA engineering Professor Vijay Gupta and his colleagues have developed "a way to reduce the G-forces a player’s brain would experience during a hard hit with just a 2 millimeter thick strip of polymer inside a helmet."
Scott Jung (who playfully admits he's a USC fan at the end of the article writes:
The UCLA-developed polymer is a special material that actually had its roots as a bonding agent for ships being built for the U.S. Navy. The polymer was shown to have the ability to withstand shocks from explosions, so Gupta, who shares a fondness for American football, decided to test the material on explosive helmet-to-helmet hits. In tests that utilize a heavy weight dropped onto helmets both with and without the strip of polymer, Gupta observed that the material reduced the G-forces on a player’s head by up to 25 percent.