Another home automation-related book that you should definitely check out is Home Hacking Projects for Geeks, by Eric Faulkner and Tony Northrup. If you're interested in creating a time-shifted FM radio, creating your own keyless entry security system, or just want to finally get control of your home theatre system, you'll find these (and others) projects described in detail.
One of my favorites is the project for remotely monitoring your pet. I think it's a great example of how to put together something cool using just a few off-the-shelf parts. In Smart Home Hacks, I describe how to accomplish this using a standalone network camera and a little Python scripting. In Home Hacking Projects, multiple webcams, motion detectors, and Perl are combined into a very clever solution. I might just mash the two approaches together for the ultimate pet-cam setup! Check it out in the book's excerpts.