David is having trouble misplacing his items. After looking into possible solutions he found a good amount of bluetooth smart tags that you can use your smart phone to keep tabs on. For reasons of not having his cell phone around all the time, and just not that interested in crazy smartphones, he started to work on his own solution.
He found these wireless tags from Nike that you attach to your shoes and your iPod can keep track of your running habits. The first hurdle was to modify the beacon to transmit constantly instead of going to sleep when there is no motion. Next he made a device to read the beacons with a little Adafruit and Sparkfun help. Full article here.