As geeky as it maybe, the Nerf Sentry Gun is bad ass, cool. When a person enters the room they must display a badge to avoid being fired on. If the badge isn’t displayed in a set period of time the gun unleashes its fury and automatically targets its prey rotating on a motorized turret left to right. The Nerf Sentry Gun was built by a few students (Jason Wright and Jeremy Blum) as part of their final project at Cornell University’s CS1114 Matlab Robotics class. Video below.