Adalight is also cool and one of the very few projects where instead of being able to just do it on a basic stamp instead, it actually benefits from moving up to a Teensy for faster refresh rates. Adalight is TL;DR picture-sensitive ambient monitor / TV / projector backlighting. The colors around the monitor change based on what's on the screen. It's a neat effect that was standard on some Phillips TVs: https://learn.adafruit.com/adalight-diy-ambient-tv-lighting/...

http://davenewson.com/posts/2013/ambilight-with-teensy-2.htm...

Also works with e.g. XBMC. I'm hoping to get mine working with my FireTV.