To avoid those moments of sheer panic that occur whenever you discover you’ve left something important behind, consider attaching one of these
to your bag/PDA/dog/toddler and put this 
in your pocket. The Mini Reminder transmitter will alert the receiver to start making a vibrating, beeping racket if you move more than your specified distance away from it. I need this thing. How many times have I raced back to a restaurant to admit sheepishly that I’ve forgotten my bag on the back of that chair? Yes…the one you’re sitting on…thanks.
via SCI FI Tech