Looking to extract a little revenge on that co-worker who’s been driving you crazy? ThinkGeek has the gadgets for you. The Annoy-a-tron, EvilTron, and Annoy-a-tron 2.0 are the perfect weapon in office warfare. The Annoy-a-tron is a small device that can be hidden around the office and set to emit one of three sounds. It comes with a built in magnet and will release a short beep in varying intervals making it hard for your target to locate. The Annoy-a-tron 2.0 ups the ante with six sounds to choose from: including the ever popular cricket chirping, and a higher 15kHz tone. My personal favorite though has got to be the EvilTron. The Eviltron is about the size of a quarter and comes equipped with some of the best evil sounds available including: sinister child laughing, unidentifiable scratching, and eerie whisper of “hey, can you hear me?” I can see this causing someone to seriously question their sanity. Assuming that they don’t find it, the battery can last up to a month. Use at your own risk and only on those that truly deserve it. ThinkGeek is also running a special on the original Annoy-a-tron at $4.99 right now.