Differential Games by Isaacs and the identically titled Differential Games by Friedman. Differential games involve the mathematical simulation of chase and evasion scenarios such as the Homicidal Chauffeur and the Princess and the Monster. These scenarios are fun to play with from a recreational perspective, but also have practical applications to e.g. warfare and optimal control theory. I'd love to do a PhD in this field.
An Introduction to Celestial Mechanics by Moulton. Not really my field, but it's interesting enough.
Yippee Ki-Yay Moviegoer : Writings on Bruce Willis, Badass Cinema and Other Important Topics by Vern. It's a book of movie criticism that will go nicely with my copy of Seagalogy: The Ass-Kicking Films of Steven Seagal by the same author.
Remember I told you before that I was rereading some of the books I read as a child? Well, don't judge me but I've also ordered Dark Moon by David Gemmell and Dragonsdawn by Anne McCaffrey. It's all about the nostalgia, yo.

Related categories:

Reddit mentions of Dark Moon