What are some of the cool features in a Mac?

I've played with a MBP, read a bunch of comparisons and seen videos, so I know about the usual things like Spotlight, trackpad gestures, Mission Control, Automator etc.

But I want to hear about other things that may not be well known but you appreciate.

e.g. Internet Recovery - allowing OSX to be reinstalled from Apple servers. Sort of like Windows network book from an IT image.

Trying to find out how different using OSX daily is from Windows, other than the features you can read about on Apple's site. e.g. do you like Finder? Do you use tags/labels? What do you miss when not on OSX?