Non-Arduino-microcontroller (PIC, STM32, MSP430, ESP8266,...) topics are also highly welcome!
Please follow the standard rules and etiquette, and only post content that relates to the tribe.
I made a cooling system for my home theater cabinet. It sits on top of my onkyo receiver, pulls air through it, and blows it out of the front. I have an RGB LED on the front to indicate the temperature of the receiver. It's nothing really advanced or anything, but it is useful to me. Also, I replaced the arduino dev board with an ATTiny84.
Nice idea! Do you control the fan speed based on the temperature?
My initial prototypes started out with that in mind; however, in my experience with the blower fans I'm using, oscillating an output to a TIP-120 caused an annoying sound in the fan's motor.