Interesting build using an RPi as the controller. The author built his own shield to control and get status on the garage door. I like the use of magnets for sensors to determine if the door is open or not. Only thing is I think an RPi maybe a bit overkill here. Thought network connectivity it provides is nice.
http://lowpowerlab.com/blog/2013/10/11/raspberrypi-home-automation-gateway-hardware-and-demo/