TagCrowd is a visualization tool that creates tag clouds based on the text you provide by either pasting or typing it, or uploading as a file up to 100 KB. It was created by Daniel Steinbock, a doctoral student in Design and Education at Stanford University.
Here’s one possible use for it. Before reading an article, you can run it through TagCrowd to get a visual preview of what it is going to cover. I did that with my yesterday’s post, and here’s what I got: