Packing for Mars: The Curious Science of Life in the Void by Mary Roach
It's Mary Roach, so no surprise that her book on space focused on how hard it is to take a crap (in space), how much engineering goes into disposing of crap (in space), and practical uses for crap on a Mars mission (including making it into radiation shielding tiles and reprocessing it into crap burgers). You'd think this book would be NASA's worst nightmare, but it's actually humanizing as well as fascinating. If you're a Roach fan you'll love it. If you haven't had the pleasure then this is a great place to start.
The Lion by Nelson DeMille
This sequel to The Lion's Game is disappointingly flat - Corey and Assad are fated to meet for a final confrontation and they do but after an initial sky diving sequence nothing really happens. There's very little tension, no plot, no struggles or setbacks for the hero or villain. DeMille really phoned this one in.
The Girl Who Kicked the Hornet's Nest (Millennium, #3) by Stieg Larsson
The second and third books could be just one (very) long book. Nest kicks off where Fire ended and slows the tempo down a bit, although not to the glacial pace of Tattoo. It's a fitting ending to the tale of Salandar, if a bit drawn out in the final sequence. Of course, a must read if you've ploughed through the first two.