Takanoha’s “Nap Alarm” is a wearable, low-cost gadget to keep you awake. The Japanese invention is placed behind the year, and vibrates should you fall asleep. The little gizmo detects the speed at which your head falls to determine if you are actually dozing off. Pretty nifty, but I still recommend stopping for a rest instead of risking falling asleep behind the wheel. The Nap Alarm sells for 1,450 Japanese yen, or about $12.