A really simple project, conceived when I was looking to mod my PC case
with RGB LED-strips. I discovered my motherboard had a header for RS232
serial comms. The idea is to hook a small Atmega board inside the PC,
leech off of a 5V and 12V supply rail, and receive commands from the PC to change
colors via the serial port.
It uses a bit-banging implementation for PWM, even though there are dedicated
PWM channels. This is simply because bit-banging allows for easily customizable
pinouts, and for the possibility to add even more channels in the future.