The Powers of Ten
I came across this link on the OLPC wiki. It's a really cool Java applet that illustrates from the edge of the universe to the surface of a proton. Check it out: http://micro.magnet.fsu.edu/primer/java/scienceopticsu/powersof10/
Click on these amazing photos to go to the Florida State Uni's Micro Magnet website.
Personally I think the ampicillin photo is the most awesome 3 dimensional abstract art I've ever seen. Look closely. It's like looking through a stereograph.
And if that's what beer molecules look like, I'd love to see LSD.