Reebok displayed its head-mounted impact indicator, called Checklight, which tells wearer how serious that last tackle really was. By combining an accelerometer and a gyroscope into a small, lightweight package, the Checklight is able to measure both the strength of the impact and how your head is likely to respond to it. Unveiled over the summer, the Checklight is available for retail now and sells on Reebok's site for $149.99.
