Today twenty years ago was when the Internet as we know it today switched over to TCP/IP.
And when you look at it's growth from then (around 1000 computers) to what it's become today you really gotta give those guys who came up with TCP/IP respect...
I mean, 20 years in the computer industry and still going strong, that's what I call future proof ;)
This article also points out many other milestones throughout the history of the Internet.