Pages - Automatically adds smaller heading styles once you’ve used the smallest displayed style (e.g. “heading 3” only appears after you have used “heading 2” in your document).
OS X - When you search specific file type, the search input adds a “kind” drop down.
iOS - When using internet on EDGE network, loading icon in status bar rotates slower than it does on 3G.
AirDrop - The icon changes from a package with a parachute to a radar when selected.
Mac App Store - While downloading a new app, the icon transparency changes according to the progress of the download.
/via Florent Gosselin
OS X - The print queue icon matches the actual make and model of the printer/copier you are printing to.
Highrise iPhone app - As it loads your account’s database, it presents you with a playable game of tic tac toe.
iOS Safari - When you’re typing something followed by a dot in address bar, pressing the .com key, will result in a perfect one-dot spelling anyway. Then when you press it longer it shows you other domain options.
/via Kyle & solonsky