I just discovered Wordle, a Java applet that creates word clouds out of text. The frequency with which a given word appears is represented by its size in the cloud, so you can look for patterns or themes in a block of text that might not be obvious when presented in a normal format. You can create your own at the site, adding text or links to a webpage or del.ici.ous site tags. The clouds can be customized by font, layout, color, etc. Once you've made your cloud, you can save it to the site's gallery, which now has over 100,000 additions. The Worldle Blog, written by the applet's creator, Jonathan Feinberg of IBM, offers a discussion. I've made a few clouds, shown below the fold. Not sure if they are particularly interesting, but these texts came to mind.
MLK Jr.'s "I Have A Dream" Speech
Charles Darwin's On the Origin of Species
Franz Kafka's The Metamorphosis