I think someone asked about it previously... One suggestion was just to wire Espruino into the buttons on the remote control, but you definitely implement your own transmitter.
The way I figured out the signals to send there should also work for your remote controlled fan (you'd need a transmitter/receiver pair). Hope that helps!
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
I think someone asked about it previously... One suggestion was just to wire Espruino into the buttons on the remote control, but you definitely implement your own transmitter.
I did this for 433Mhz RC sockets: http://www.espruino.com/Remote+Control+Sockets
The way I figured out the signals to send there should also work for your remote controlled fan (you'd need a transmitter/receiver pair). Hope that helps!