Cryptonomicon

Very cool book. This is probably the first work of fiction that I ever read with realistic (and detailed) geekspeak. One of the primary characters is a UNIX network/hacker type, and Stephenson doesn't shun specifics when it comes to what the guy is doing on his computer. He also goes into detail on encryption itself. A few pages of the book actually read like a text-book on the subject with formulas and everything. If you aren't technical, you might not appreciate this book. However, if you are a computer geek like I am, you probably won't be able to put it down.