I made a TV Simulator for my Arduino using a 7-Segment shield (for the RGB LED). It’s pretty simple. It just changes the brightness of the 3 colors red, green, and blue to a random setting after a random amount of time. The brightness of each component color (hence the overall brightness and mixed color) is controlled by pulsewidth modulation of digital output pins 3, 5, and 6.
I gotta hook this up to my single pixel display Processing sketch some time.
A TV simulator, by the way, makes it look like there is a TV on in a room. It’s definitely not my idea, but I don’t remember where I saw it.
Here is the sketch.