[lukevanoort]

It's a good goal, but I highly doubt many, if any, big websites will go black. The fact is web design is about quickly delivering information and content as effectively as possible to people; white on black is harder to read than black on white. Macs have a feature to invert screen colours, which would work well for this because people could turn it off if they needed to (and could save power when word processing). You might have better luck trying to convince the development communities/companies of major browsers (like Firefox, Safari, Opera, and Konquerer [Microsoft is hopeless to try]) to add a hotkeyed "invert tab" feature.