To call [Carnivore's] home automation project impressive would be an understatement. He’s pulled together a system that is fast, well presented, and easy to use. To interface with items in his home he’s using X10 modules, and this example simply switches some table lamps. But the underlying setup seems incredibly polished and should be a snap to extend for just about any purpose.
The guide linked above has all the gritty details, but the best overview is provided in the video after the break. [Carnivore] shows off the Windows 8 machine that acts as the server. It has am X10 transceiver connected to communicate with the appliances. He can control the system from the screen seen above, but everything can also be accessed from his Android phone. Communication between the two is handled by Google Talk, an instant messaging application — but the commands are home screen shortcuts and don’t need to be typed into the Google Talk app. He modified the source code of a program called TweetMyPC to use the Google Talk API which looks for keywords in received messages. The lag on an instant message is far lower compared to SMS or Email so commands are received very close to real-time. Feedback is sent from the server to the phone using a text message.