Last year, I just mentioned Wordle - it was a relatively new resource at the time.  This year, it has become a favorite of many teachers who are using it for a variety of instructional strategies. 

Basically, you copy and paste the text of a document into Wordle and it produces a visual representation of the words used.  It looks cool, but it can also provide an interesting story.

Wordle Resources

• 38 Ways to Use Wordle
• Guess the Wordle - A website dedicated to instructional uses of Wordle!