Reading Adaptive Path, I ran into a link to Wordle. It's a really fun a web app for creating word art out of whatever text you feed it. The words are sized in proportion to their frequency, and there are all sorts of settings you can fiddle with, including fonts and colors. This is one I made with the first chapter of Orwell's 1984:
I love the idea of word art programs, but I always walk away disappointed. This one definitely lives up to the hype, though.