geekrex @ instructables.com shows us how to use ESP8266 Wifi module for home automation. He writes:
ESP8266 is a great thing for starting to Wifi And IOT. It is also cheap and be used for making cool projects connected to the Internet .Learn how to make a simple IOT Project with it ESP8266 WLAN Module could be a self contained SOC with integrated TCP/IP protocol stack that may offer any microcontroller access to your WLAN network.
ESP8266 Wifi controlled Home Automation – [Link]