If you've ever used a cordless phone's "pager" function to chirp out a homing-signal from the couch cushion or back porch, then you're sure to appreciate the "Now You Can Find It!" Wireless RF Electronic Locater from The Sharper Image.
It's bundled with single, four-button transmitter and four separate locators which attached to anything small and elusive with either a key ring or adhesive; ideal for the TV remote, car keys, cell phone or PDA -- or your pets and kids, for that matter.
With an effective range of 30 feet good for a room's length or two, the transmitter will also detach from its mounting bracket and allow you to scout for whichever wayward device room by room.
The transmitter runs on 2 AA batteries (sold separately) and the receivers run on lithium coin-cells (included).
Mind you, they're good for about a year before they go flakey and either break or just give up the ghost.