The winner of last month’s MAKE gadget design contest was this beast by Rick Prescott: A Nerf machine gun that automatically detects hapless warm-blooded people in the vicinity (sadly, ineffective against zombies), swivels, and rapidly fires darts at them.
An idea sparked in my mind one day while walking the toy gun isle in a store with my kid and later that evening learning of the workings of a thermopile array while surfing the internet. The result is this infrared seeking sentinel which joins a realistically priced infrared sensor to a realistically operatable Nerf® machine gun to create a slightly less deadly yet still highly deterring automated machine. Personally I have grand plans to deploy the infrared seeking sentinel facing the entrance of my work cubical in order to speed interaction with less desirable visitors.
Watch it in action: