My 4 year old daughter's cheap nightlight quit working. Of course, everyone has to at least attempt to build a replacement LED light...right? I wanted it multi-color so she could choose her favorite colors. I had a (Adafruit) Circuit Playground Express laying around so thought it would work nicely as a quick fix with its onboard LEDs. After experimenting with various enclosures I noticed that the CPE fits perfectly in one of those chewing gum dispensers that you find at the grocery stores. Pretty awesome!!! Has the added benefit of being a "diffused" enclosure for cutting the edge off of intense LED light in a dark room.
Added a "Pot" to control the brightness and a push button to change colors. A little hot glue to hold it in place inside the container, a little CircuitPython, and pure fun for a 4 year old. Quick and easy!
Adafruit's Circuit Playground Express fits perfectly
Added Pot and push button on top and cut hole for USB power