Just discovered Tagxedo, which is a far more flexible tool than Wordle for making word clouds/visualizations from text. The catch is that Tagxedo requires Silverlight, a Microsoft browser extension…
With Tagxedo, you have a lot more control over shape, which words are included, and potential sources (Tweet streams, URLs, etc). Definitely worth checking out!
Here is a cloud I made from the Twitter feed generated during the Oregon Folklife Network‘s launch-symposium, “Public Folklore in the 21st Century“:
Click on the image or follow this link to get to a “live”/larger version on the Tagxedo site…