I just bought Cryptonomicon by Neal Stephenson for my summer reading. Shannon and I are going camping this weekend, then a week+ long trip a couple weeks after that, so I needed something 'portable' for my reading pleasure -- I say 'portable' as Cryptonomicon weighs in at over 1100 pages, and as for a trade paperback book, its quite thick and bulky.
At home I've started to read Blackwood Farm by Anne Rice which has the return of Lestat to the Vampire Chronicles -- and not just a cameo. But just like most of my Anne Rice novels, its in hard cover, and I'm not about to bring a nice hard cover camping with me.
Both appear to be really good books, and a change of pace from the light fantasy/sci-fi books I've been reading lately (Eragon, Harry Potter, the Holka series, Human Edge)
For fun, see if you can try to crack the solitaire code: UKIEI ANQEE OMAPR
Hint: Solitaire is a real encryption algorithm that is used in Cryptonomicon.