Pearl, my beloved labradoodle, dutifully watched me build myself a new house for the past three years. So when I was almost finished, I decided to build her a place of her own. A standard model just wouldn't do, though, so I went a little overboard. After creating the design with CAD software, I added a solar hot-water radiant-heating system and made a green roof that retains rainwater, creates oxygen, and improves insulation. Then I decked it out with a few other touches, including some colored LED lights to brighten things up and a Web-enabled wireless video camera that lets me keep an eye on Pearl from my computer or phone. That's plenty of features for her, but the doghouse has one extra benefit for me: The battery that powers it also powers all the low-voltage exterior lights on my property.