ThinkGeek never lets us down in the way of oddball gadgets. Just in time for the holidays is their new TannenBomb Prank Holiday Ornament. That’s right, a prank holiday ornament. This clever little globe has a bit of hidden technology contained within. While sitting in its box, or even lying out somewhere, it looks and acts just like any normal decoration. The fun begins when they hang it on their tree.

The act of placing it on a tree (or a hook) activates a trigger, which tells the device to play one of four random sounds at random intervals. At any given point of a day, people will hear a beep, mosquito tone (ultra high frequency nerve grating sound), a Christmas cricket or an elf giggle.

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$11 sounds like a reasonable price to pay for driving your friends or loved ones crazy this holiday season. Heck, it even looks like a stylish ornament, what with the zombies and robots on it. Were it not for the fact that it would bug the crap out of me, I’d hang one up on my tree.

To startle your unsuspecting victim, simple pull the pin and lob your grenade in their general direction. The Sonic Grenade lets out an ear-shattering sound that should scare (and annoy) the bejesus out of just about anyone who’s not legally deaf. As an added bonus, your unknowing victim cannot shut off the grenade without the pin. It’s just $13.95 from Firebox.com.