Knowing almost anything, from anywhere in minutes. The Encyclopedia Brittanica of everything is at your fingertips and there is almost no reason not to know how to do something, how something is done, who does it, why, etc, etc, etc...
Still blows my mind that I can ask a question on Google and within a fraction of a second it has hundreds of answers from a collective depository of knowledge and information that is almost unfathomable. And, as the "internet of things" builds out, people will lose sight of how life existed without the internet. My kids (17 & 18) have no REAL understanding of how life existed before the 21st century. It is as if they are hearing about things from history books when discussing how life was when I was growing up in the late 60s and 70s!
In short, the world comes to them in any form they want, whenever they want. THAT, for me, is the miracle of the Internet...the world in my hand!