The ThinkGeek Ringtone Annoy-a-tron

Enter the Ringtone Annoy-a-tron. Like our standard Annoy-a-tron, this small device can be hidden anywhere: in a drop ceiling, under a desk, behind a cubicle wall, under a chair. The attached magnets make this even easier! Set the volume and select your ringtone from a selection of five familiar sounds. Then stand back and try to keep a straight face as the people around you search desperately for the phone that's ringing at random intervals throughout the day. One battery will last you up to 4 weeks... or until someone finds the device and smashes it with their Hulk-rage. Hide it well, friends!