Fadeout is a simple plugin to make your page fade to black or white. There are several features such as the ability to exclude the fade from the homepage and/or exclude by menu ID. There is also 2 sizes, small and large and 2 colors, black and white.
Fadeout uses jQuery to remove the fade when you get to the bottom of the page. This way no fotter links or content are ever covered up. You can see fadeout in action on the bottom of this page.