Wallets and other valuables tend to grow legs and walk off sometimes, only to be found two weeks later between the couch cushions or in the trash. The worst case scenario is that someone actually walks off with your stuff, while you cluelessly sit at the bar enjoying a Friday night of binge drinking.
Preventing this from ever occurring is as simple as utilizing the Smartphone Security Sensor ($69). By downloading the free app, the motion sensor syncs to your smart device via bluetooth 4.0 and vigorously alerts you to any thievery of your stuff by setting off a series of flashing LED lights, sensors, and vibration/audible alerts. It works at up to 20 meters away, has a 4-month battery life on a single charge, and works perfect with your wallet, keys, luggage, and anything else of importance.