I found another cool project for IoT and made with the ESP8266 by mcmchris
on Instructables. That post is a tutorial where you will learn how to build your own light switch and fan dimmer in just one board with the microcontroller and WiFi module ESP8266. So, a great project for IoT. be careful, this circuit handles AC main voltages. The crator posted a video tutorial that shows you the whole process.
In the same post, he is sharing all you need to build this. The schematic, the PCB GERBERs, the parts such as resistors, capacitors, modules, etc and also the code that he will use. All you have to do is to downlaod the PCB, manufacture it, solder the components and test how it works and control your light and AC fan from the internet.