Secret Worlds: The Universe Within

I came across a page done by the Optics and Microscopy department of Florida State University.

The Universe Within explores the universe from 10 million light years (1023 meters) from earth to 100 attometers (10-16 meters).

A cool display of the powers of 10 and metric prefixes.

For the scientifically minded, there's also a pile of other interesting stuff on the page (including lots more Java demos).