Classical art, with all the annoying chatterbox people and flappy angels etc edited out. Bit of peace and quiet… and an opportunity to see how the basic layout sans-subjects was done. The Last Supper above, is a study in Fibonnaci. Golden Means everywhere.
Mind you, my favorite one is more to do with Pi than Phi.
Ceiling Cat had nothing on these guys. A Ceiling Jesus, some randoms, some cherubs and a ceiling-peacock.
Speaking of Pi, check out these Aquatic Micro-Planets