Link: ThinkGeek :: The ThinkGeek Annoy-a-tron.
...it's very effective at disturbing that guy in the sales department or your "friend" down the hall. With its thin design and embedded magnet for easy hiding, the Annoy-a-tron can be placed in a variety of locations. Select one of the three sound choices (2 kHz, 12 kHz, or alternating) and push the switch to the on position. Place it in a proper hiding spot and let the "fun" begin.
The Annoy-a-tron generates a short (but very annoying, hence the name) beep every few minutes. Your unsuspecting target will have a hard time 'timing' the location of the sound because the beeps will vary in intervals ranging from 2 to 8 minutes. The 2kHz sound is generically annoying enough, but if you really really want to aggravate somebody, select the 12 kHz sound. Trust us.
