Simple. A writewatch with some sort of proximity sensor, attuned to some unique aspect of the owner. It would play a tune when the user got to far away. Perhaps "We'll meet again" - giving a plesant reminder that it has been left behind.-- mcscotland, Apr 30 2001 Never Lose Anything Again http://www.halfbake..._20anything_20againI explored ideas relating to this, using RFID tags. It contains a link to a scientist working on this. [GusLacerda, Apr 30 2001, last modified Oct 05 2004] How about strapping it onto your wrist?-- DrBob, Apr 30 2001 Dr Bob: Nice one.-- oobersteph, Apr 30 2001 Why a wristwatch? I actually need this device for my pen, walkie-talkie, walkman, and car keys.-- centauri, Apr 30 2001 with a backup chain connected to earring and/or navel piercing-- thumbwax, Apr 30 2001 Hey, why not just tatoo a watch on your wrist. You'll never lose it (unless you want to pay a plastic surgeon $1000 a square centimetre to burn it off with a laser) and it will be right twice a day - guaranteed.-- roinek, May 01 2001 I think there's a bakeable idea in here.
Instead of detecting proximity to the owner the wristwatch could work another device - say an electronic organiser - as could all the other devices you have. So if anything that you should have on you all the time starts fading into the distance it can set off an alarm.
This could be achieved cheaply with small supergluable transponders or expensively with a radio system like Bluetooth.-- st3f, May 01 2001 PeterSealy Is Generous Using Existing Technology?-- angel, May 01 2001 [UnaB]: I actually knew that :-) One horse, no Starbucks, but we *do* have jewellers. I just thought you might be suggesting a new method of wealth distribution.-- angel, May 01 2001 random, halfbakery