I feel terribly guilty in advance. If you check out this website (found via the New York Times Paper Cuts blog) I doubt you will get much work done today.
Wordle generates word clouds from the text you feed in, and then you can play around with colours and fonts and so on.
This is what happened when I fed it a couple of short short stories I'd written. (Click to enlarge and admire fully.) :
You can try it with a whole book. This is Moby Dick :
If you make an extra nice one, please link it in the comments!