If you do a quick search for word cloud, you'll see so many different types. I recommend picking test text & pasting it in each text box to see the result.
This site provides an overview of the DIAL-e framework developed by Kevin Burden and Simon Atkinson. It includes a great introductory video on the project. "The framework was developed as part of a UK project, sponsored through the Joint Information Services Committee (JISC), to encourage academics and other educators to adopt digital artefacts (in this case video) as part of their teaching, learning and research strategies. Simon and Kevin have three papers about this at the Ascilite conference. I really like this framework and think it has great potential. I think it is a good example of a 'design schema' i.e. a framework to enable teachers and designers to think differently about learning and teaching.