Heh, I’ve added an alternate stylesheet to my site. You’ll need Mozilla to view it – go View > Use Style. If you’re using IE, the glutnix chicken logo and the webfroot network button will be gifs, otherwise they will be 32bit alpha’d PNG files. The CSS controls the checkers and the background image, as well as the colours. Rather simple really.
UPDATE: Added a ‘toggle alternate stylesheet‘ link at the bottom of the side – click to switch to the alternate stylesheet for the rest of the session. Might switch to cookies instead of session though.