Voice recognition is no longer in infancy, especially since Siri just  launched on the new iPhone 4S (although similar technology is available  on Android too. This project shows you how to use it to automate your  home without spending big bucks.
The core of this project is a VRBot speech recognition module.  Next,   the project creator used some low-cost wireless light switches (you   could also use relays).   The VRBot speech recognition module recognizes  32 custom voice  commands.  Once a command is recognized, a wireless  switch is activated  via a radio receiver.  The setup is simple after  you spend some time  understanding the wireless communication protocol  between the different  modules.  See the project blog to engineer the whole thing yourself.

