This article from the Linux Journal explains how to build budget home automation and security system using chip hardware and Python programming. The system contains Serial I/O Kit, Mier DriveAlert, Water Alarm and Webcam. The author gives a few examples of Python code and many ideas. So, you can expand it by yourself to get working system according to your desires. And who knows maybe it’ll grow to some well-known system like MisterHouse or Plutohome.