When he was a kid, somebody brought Sean this toy Tiki mask back from a vacation. It's been kicking around our house for years now. I finally figured out something to do with it. I stick some Neopixels in ping-pon balls behind the eyes, and the color can be controlled (over Bluetooth) from an app on my phone. I'd been looking for an excuse to play around with a Bluetooth receiver connected to an Arduino, and this turned out to be just the thing.