When Lion released its cockamamie Address Book and iCal UI, I found the apps to be far less usable than the Snow Leopard counterparts.
Mountain Lion made the functional again while renaming them to Contacts and Calendar, respectively, but the apps still have a cockamamie look to them.
These UI edits by
Shtekeris over at The Verge’s forums are elegant, functional, and simply beautiful.
Apple, please hire this guy.