Brian Kernighan's terrific book about computation and communication for the layman is out. It is called D is for Digital and is a bargain at $14.95. It's modeled on Physics for Future Presidents, and is a worthy analog in the realm of the digital. Brian wrote most of it while he was on sabbatical at Harvard last year so I had the privilege of reading drafts, and it is everything I would expect from him -- clear, funny, thoughtful, and containing quite a few profound analytical insights that enlighten the pro as well as the casual observer.
Available from Amazon.