(Video Link) 

Global Link manufactures an intimidating security system. Laser beams that sweep across a room. Lights flash. An alarm beeps. And it's all fake.

The premise is that the visible and audible presence of the system deters break-ins. Some thieves decide to go elsewhere rather risk a target that is appears heavily guarded. The system thus reduces, but not eliminates, the possibility of a break-in. 

-via DVICE