The NY Public Library's new Stereogranimator site: a novelty or an abuse of parallax? (Warning: do not use while taking cold medication.)
The Stereogranimator site is hands-on; you can create your very own disturbing effects.
For an explanation, see this blog post on the NY Times website.
It's perfect for people with too much time on their hands! (Me, I already feel bad that I took this much time posting about it.)