Just wanted to post a project I made a while back using six photoresistors + an Arduino. I feel like I keep discovering new uses for them! I call it an Illumaphone. (Here’s the YouTube video.)
Basically, by moving your hands above the cups, you can control volume and vibrato. Each cup is a different note. It’s kind of like a theremin, but with discrete pitches! If anyone is curious, I describe it in more detail in a blog post here.
Lately, I’ve been having a lot of fun combining simple sensors with ChucK, a musical programming language. I highly recommend it for anyone curious about electronic music. 🙂