[Ronnie] built a laser trip wire complete with an LCD screen and keypad for arming and disarming the system. The brains of the project is an Arduino.

In this project, we create a joystick-controlled laser by connecting two servos to a joystick and using this setup as a pan-and-tilt controller for a laser pointer.

Sure, you could opt for a laser tripwire that puts intruders on blast via Twitter, but there's something to be said for the simplicity of the latest security system to come from Instructables user ...