Way back in August 2006 a teacher called Karl Fisch at Arapahoe High School in Centennial, Colorado, USA created an 8 minute PowerPoint presentation with some music.  It aimed to highlight the rate of change of the world we live in, and remixed content from David Warlick, Thomas Friedman, Ian Jukes, Ray Kurzweil and others.  I blogged about it November 2006.  It went "viral" through bloggers and YouTube so that by June 2007 it had been seen by 5 million people online.  As of today, versions of it have been seen by more than 20 million people.   

Here's version 2.0 from June 2007: