If you've ever lost your iPhone -- or your keys, for that matter -- you'd likely be happy for a way to help prevent that from happening again. Kensington's BungeeAir Power Wireless Security Tether + Battery for iPhone 4 ($100) is made to be just that. The solution contains a few different pieces: a 1500mAh capacity battery case, a key fob, and a free BungeeAir app. When the iPhone 4 is inserted into the front bumper-removable case, it's pretty well…
