Cycling can be dangerous, especially if you ride at night or in busy metropolitan areas. To help, a startup called Cosmo Connected is working on a smart light that clips onto the back of your helmet. Eight LEDs -- four red, four yellow -- are positioned in an oval shape. By default, they're set to an "always-on" position so that you're clearly visible in the dark. An accelerometer inside will know when you're braking, however, and warn fellow cyclists, drivers and pedestrians with a more intense light.