I have a whole drawful of 3D printed parts. many are protective cases for small boards like load cell amplifiers or thumb sticks
A simple 45 degree angled case for a PIR motion detector
A Printrbot fan shroud that might work well on the CNC router too
The best part is being able to customize the cases to fit the board like this BLE thumbstick
Its a nice snug fit and the end cap hold pretty well with no glue needed
The leds show right through the side. of course it does help that at that particular location in the case the sidewall is thinner that the rest of the case. I may remove that aspect from the next case i print since its not really necessary.