Here's Hemingway's famous story, "Hills Like White Elephants," in which two characters sit around a train station bar discussing a potential abortion without ever saying it outright.
Obviously, "abortion" is nowhere to be seen. Nor are any character names, because these characters are unnamed. But "girl" and "want" are enormous, with "man" and "please" not far behind. Other prominent words include "station," "table," "beer," "anything" and that sad little protest "fine," which the girl assures the man she feels by the story's end. In this word cloud, we have all of Hemingway's narrative furniture -- the setting, the activity the characters are engaged in, and the emotional tenor of the negotiation that's taking place.
Not a bad teaching tool -- definitely one I'll remember when I'm teaching again. But word clouds don't just help us see why the classics are great. They can also be a way of checking new work -- helping writing students to vary their own word choice, for example. If, say, the word "individual" shows up big and red in an essay that has nothing to do with political philosophy, the writer might have to ask herself why she can't come up with a more specific word. (Probably because she watches too much ESPN. But that's a topic for another day...)