Nothing says hilarity like making somebody else physically ill. That's the idea behind Sonic Nausea, a tiny device that makes people sick to their stomach when they're within it's range.
You simply plug the little thing into a 9-volt battery and then it pumps out "ultra-high frequency soundwaves which soon leads most in its vicinity to queasiness." While I'm not quite sure about whether or not soundwaves can make you sick to your stomach, this is the perfect way to get back at your boss, annoying neighbour or pregnant girlfriend/unborn child. The possibilities are endless, really. [Product Page via BB Gadgets]