My husband has been doing various computer projects for a while now. He has a little robot he’s working on (Chappie, after the movie), and he’s been working on a color changing light for my bike that would turn red when a car got close. I don’t know how to do most of what he’s doing, but I still think it’s pretty darn cool.
For example, he’s got a strip of LEDs set up to react to sound. It can be a bit annoying when watching television shows, but it’s really nice when we’re listening to music. Automatic dance party lighting!