Riley,
I appreciate the beauty of some moonphase displays, such as the pictured AL&Ss and the VC Malte Chrono Perpetual, and I understand how one might appreciate the inventiveness of the mechanisms by which they work.
May I ask whether this complication is also valued for the information it imparts? If so, why one would be interested in knowing the phase of the moon? The only ideas that occur to me are related to navigation at night or selecting the timing of night operations (e.g., to plan crimes or military operations). Are there other rational uses of the function?
Park