“Now You Can Find It!” is a device that comes with a set of plastic tags that you attach to easily misplaced items: press the button on the hand-held locator device and those tags start beeping. The next step, currently in development, is to make loseable items (be they cellphones or wallets or anything else) with electronic tags built in. DIPO, a French company, has a device that takes an even more proactive approach. It sends out a signal to tagged items every few seconds. If you move too far away or try to leave without them, they will start to beep, vibrate or flash unbidden, found before they have a chance to be lost.

The technical caveat for all these devices is that they tend to have a range in the area of 30 feet — perfect for something hidden in a cluttered office cubicle but somewhat less so for something abandoned on a city bus. As for Global Positioning System technology, with which a new generation of watches and pagers is being equipped, it is notoriously ineffective at penetrating buildings.
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