Have you ever wished that you had a robotic weapon like the Sentry Gun from Team Fortress 2 to protect your office? The folks behind TF2 over at Valve thought that would be cool, so they got the geniuses at New Zealand's WETA Workshop to build them one.
WETA Workshop makes a lot of the weapons and other props you see in major Hollywood movies, and what they have come up with for Valve looks awesome. It will track people entering the building, and can pan a tilt to follow their every move. The video shows it making sounds and flashing a red light when it "fires", but I wonder if there might be a secret mode that switches to real rounds if it detects someone from Bungie trying to sneak in.