From Spaceman Glen. These are very cool. The first one has a giganto java applet and I had trouble getting it to load, but if you have a decent-sized computer, it’s worth it – It’s Molecular Expressions’ Power of Ten. It’s basically a site that starts you out in the Milky Way 10 million light years from earth, then moves you 10 times closer and 10 times closer and you eventually get subatomic inside a leaf on earth.
The other one also rocks, if you like space and stuff. It’s from Australia and it’s called The Best of Hubble. It takes you on a tour of some amazing Hubble images with some neat spacey music. Very cool. Very, very cool.