I didn't make it to ACL2008 back in June, but Ani Nenkova, who was the tutorials chair, recently sent me a link to some really terrific slides from a tutorial by Christopher Collins, Gerald Penn and Sheelagh Carpendale on "Interactive Visualization for Computational Linguistics". (Warning: it's a 13.8 MB .pdf file).
Here's their first figure:
(click for a larger version.)
Of course there are Wordle-like things as well, but I really like the idea of 567,437 cancer abstracts viewed as clusters of stars. Though that particular picture looks more like a fluorescein-stained micrograph…