Technically I should be posting about this next week, but eh, close enough
This is the Konstantin Chaykin Moscow Comptus Easter Clock
This thing has 26 different indications on it, including the date of orthodox easter, starmap, analemma, and length of day
It's incredible
seriously, this thing is so incredibly complicated the fact that it has a tourbillon is at the bottom of the feature list
'cause of course it has a tourbillon