Word Constellations

The Visual Thesaurus, by Thinkmap Inc., maps relationships among words in three dimensions, rotating to reveal the entire universe of related words. It's like the class know-it-all, but more fun: Placing the cursor over a word (colored by part of speech) reveals its meaning; placing it between words shows how they are related. Clicking on a meaning reorders the universe with the new word at the center. Online subscriptions are $11.95 a year (www.visualthesaurus.com).