Look hard, and you can see TLPI
This is fun... I'm fairly certain that the guess by this redditor about what you can see sitting behind the laptop in this photo (taken by John Snyder, and used in this 21 Feb 2012 Wired article) is correct. Probably, it's the copy I gave Linus last year. It's nice to know he held on to it, though I'm not so sure there's so much in the book that he doesn't already know.