Sunday Reverie

Most of you likely know of Steve Strogatz's book, "The Calculus of Friendship," about the touching lifelong relationship between Dr. Strogatz and one of his high school math teachers.
Today, for a Sunday reverie, I'll just link to this 2009 RadioLab episode (15 mins., entitled "Calculove") about the story… worth a 2nd listen if you've heard it before (or already read the book), and definitely worth a first-listen if you aren't familiar with the story:

http://www.radiolab.org/story/91700-calculove/