I worked with Hellicar and Lewis, Nexus Interactive and the extremely talented Roxlu on a project to visualize what was happening on twitter in realtime as the talks at TED were going on.
The users could interact with a cloud of tweets displayed on the screen by putting their hand in a well and stirring. They could reach down deep into the well to pick out subtopics to filter the twitter stream.
It’s in openframeworks, and uses a kinect for the interaction. Most of the caustic visual effect is detailed in an earlier post here (“Poor Man’s Caustics”).