Someone once observed that the moon is a harsh mistress. But that doesn’t mean you can’t keep track of her, specially with this awesome moon phase clock that [G4lile0] designed and built.
It uses a 3D printed moon model combined with a series of LEDs to create the phases. These LEDs are driven by an Arduino that calculates the phase to show, as well as driving a small OLED display that shows the date and time. There is even a party mode for all of those lunar raves that you host.
[G4lile0] has done an excellent job of documenting the code that drives the lamp, so it would be easy to add features, or adapt this design to show the phases of another moon or add other features. It’s an excellent overall design, and kudos to [G4lile0] for doing it all with open source tools like FreeCAD.