The ThinkGeek Annoy-a-tron, clearly aimed at the "office joker", is said to be devilishly effective at disturbing that guy in the sales department or your "buddy" 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 for some devious office shenanigans.

Simply select one of the three sound choices (2kHz, 12kHz, or alternating) and push the switch to the on position, then 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 or so.

Your 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.

ThinkGeek says the 2kHz sound is annoying enough, but if you really, really want to aggravate somebody, select the 12kHz sound which is worse.

So, now you can drive your co-workers slowly mad - and even if they do locate the little gadget - it's fairly unlikely they will be able to work out what it is, or even link it back to you.

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