Edward Tufte changed the way I taught classes and delivered presentations.
I wrote about the Tufte class I attended in June 2008 in my post The Best Single Day Class Ever.
Since then I've written a few other Tufte posts here. The most recent post, from 2012, was Netanyahu Channels Tufte at United Nations. I explained how Prime Minister Netanyahu literally drew a red line on a diagram during a speech to the world.
Today in my Twitter feed I saw that Edward Tufte himself reTweeted my link to that 2012 story. I am so thrilled that he read it, and presumably knows that his work changed my professional life and how I interact with audiences. Thank you sir.
And yes, this does sound like a "fan boy" post. I still recommend you take his one day course, whenever it's offered nearby. I see he will be in the DC area 31 March - 2 April 2015.