Most popular GNXP post of all time?

Was talking to a friend and mentioned offhand that the most popular GNXP post of all time was written in 2010 very casually and because of a question on Twitter posed by Jason Goldman. At 700,000 Google Analytics sessions it periodically still gets bumped up by places like Reddit.

The book to the right is a pretty big clue. Can you guess the post? I’m posting the link in the comments below….