AirDrop - The icon changes from a package with a parachute to a radar when selected.
/via Niels

AirDrop - The icon changes from a package with a parachute to a radar when selected.

/via Niels

iA Writer - The icon adapts when it is displayed in different sizes.
/via Simon

iA Writer - The icon adapts when it is displayed in different sizes.

/via Simon

Mac App Store - While downloading a new app, the icon transparency changes according to the progress of the download.
/via Florent Gosselin

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.
/via werm

OS X - The print queue icon matches the actual make and model of the printer/copier you are printing to.

/via werm

OSX - When you select a folder the icon changes to an open folder.
/vuia okgeometry

OSX - When you select a folder the icon changes to an open folder.

/vuia okgeometry

VisualHub - Installation window: Put app inside the Applications folder, put User’s Guide inside your brain.
/via Nikolay

VisualHub - Installation window: Put app inside the Applications folder, put User’s Guide inside your brain.

/via Nikolay

Mac OS X - When an iPod is connected, the icon matches the model - even the color.
/via Ben

Mac OS X - When an iPod is connected, the icon matches the model - even the color.

/via Ben

OSX - The little red close button displays a darker circle inside when your document has unsaved changes.
/via Sabo

OSX - The little red close button displays a darker circle inside when your document has unsaved changes.

/via Sabo

Chrome (Dev Channel): Displays “Hold ⌘Q to Quit” instead of immediately quitting to make sure you didn’t intent to press ⌘W.
/via Micheal

Chrome (Dev Channel): Displays “Hold ⌘Q to Quit” instead of immediately quitting to make sure you didn’t intent to press ⌘W.

/via Micheal

Reeder for Mac: Settings window turns semi-transparent when changing appearance settings.
/via sklppr

Reeder for Mac: Settings window turns semi-transparent when changing appearance settings.

/via sklppr