Roget (of thesaurus fame) is rolling over in his grave, because VocabGrabber is in da' house! I copy/pasted text from a few recent blog posts and got a visual map of my word usage, analysis, relevance, and I can dig into specific words for richer interaction with my vocabulary.
This is a powerful tool for a student to analyze work in a non-threatening way. Kids invest a lot into their writing, and live under the pressure of grading and the whole "my grade=my sense of self-worth dynamic." (OK, I am writing this on Sunday afternoon, and I am ready for a nap.) I can imagine this might also be a powerful way to study the classics and the word choices of the great authors.
I love tools like this because they are relevant to how students process information. This relevance also means they have the opportunity to view their work as relevant, and not something to be turned in and forgotten. Analysis like this is critical to intellectual growth. The colors are pretty, too. Time for a nap ;)