Why the entire layout is black.

No, the layout of the page isn't black because I am a tortured soul nor do I believe that black is slimming. For proof black is NOT slimming, please head to your local shopping mall and look at the whales in black spandex tights. Back on topic, my page is black due to it's energy conservation properties. It takes less power to light up a black pixel then it does a white pixel, the less power it takes to light up the pixels, the more energy saved.

Enter, Blackle. Blackle is a Google based search engine that is essentially the same but instead of being the trademarked white home page with bright coloured letters, it's black. Blackle has this to say from their site:
In January 2007 a blog post titled Black Google Would Save 750 Megawatt-hours a Year proposed the theory that a black version of the Google search engine would save a fair bit of energy due to the popularity of the search engine. Since then there has been skepticism about the significance of the energy savings that can be achieved and the cost in terms of readability of black web pages.

We believe that there is value in the concept because even if the energy savings are small, they all add up. Secondly we feel that seeing Blackle every time we load our web browser reminds us that we need to keep taking small steps to save energy.

Check out their site and maybe consider switching your homepage to Blackle from Google. It's a very minor step in saving a little bit of energy.