Using a word cloud generator is a great way to develop vocabulary, spelling, create objects to insert into a variety of presentations or a multitude of other uses. These are three of my favourites:
If you want some great ideas for using word clouds try this blog post by Michael Gorman called “108 Ways to use Word Clouds”
As great as Wordle and Wordling are, I think Tagxedo is even more fun. A little more complicated to use but well worth it. You can create word clouds with longer text and in many more shapes. You can even import shapes of your own from pictures on your computer or the web. You could use famous poems, speeches, documents, or any sort of text you can think of.