New Book: Project Mu Archives
The players of Project Mu (the Matrix-inspired ARG I helped produce 3 years ago) wanted to create some way to communicate the experience they'd had, so they came up with a novel idea: Write a book about it.
The result was the Project Mu Archives, which just became publicly available in book form today. I've actually held this thing in my hands, and, besides being absolutely gorgeous, it's an unparalleled account of an ARG from rabbithole discovery through endgame, from the players' point of view.
As far as I'm aware, this is the only resource of its kind out there, and if you're interested in the Player Experience of an ARG (which frankly not very many people seem to be, lately), you should definitely pick this up. It walks through discovery, puzzles, story, events, and how they impacted the lives of those who played.
Not a light read, but a must-have for academics and would-be puppetmasters alike, I can't recommend this book enough.