Joe Bowers sends this in:
I set up an Arduino to read the notes on Guitar Hero and flash an LED to that corresponding note. I used this ambient light sensor, from Sparkfun to read the changes in value on the screen. When something bright flashes in front of it, the Arduino will turn on an LED for as long as that brightness is there.
I love the stands he built to position the sensors in front of each fret on his TV; they’re modified plant sprinkler stakes from the hardware store!
Joe’s ultimate plan is to have this play Guitar Hero for him.