It’s been less than a year since the ESP8266 WiFi Module was released. This is a chip whose original data sheets were only available in Chinese, could only be controlled through AT commands, and was (originally) only sold through Seeed Studio and other various Chinese retailers. It had one thing going for it: it was five dollars. For the price of a crappy sub, you can blink an LED from the Internet. Needless to say, the ESP8266 is now very popular.
[David]’s project is making great use of the relatively meager pinout of this module. He’s built an 8-channel relay controller with a WiFi interface to control industrial equipment. It’s a great project. Check it out;