skyeriding
901
Here are some:
The JLC Duometre crowns are very refined with the recessed logo.
Grand Seiko also has nice recessed logos. Same goes for Credor (Eichi II).
Onion crowns of FPJs are also visually interesting with the way the light reflects off it to give an illusion of a "spiral".
For sheer attention to detail? Vianney Halter crowns with the little "rivets" are some incredible attention to detail.
Not so much about aesthetics, but functionally the Habring COS "Crown Operation System" makes for some of the stealthiest chronograph controls ever!
http://www.habring2.com/index.php/en/collection/chrono-cos
The Ulysse Nardin freaks have interesting "crowns" - as the entire bezel is the crown.