TwitterStorm is a realtime 3d Twitter visualizer. It was written for the UT Austin Yahoo HackU hackathon event over the course of a day. It took me about eight hours to make. It tied for third place.
When you first run the program, you see an flat plane. Tweets from a few seconds ago fall down from the sky as boxes. Where they are placed depends on the length of the tweet (the short axis) and how many followers the user has (the long axis). Over time, you can probably pick out some trends.
Use the mouse to move the camera around. Left-click dragging will change the angle. Left+right click dragging will pan the camera around.
On the technical side: I used Processing's 3D features with the PeasyCam and Twitter Stream libraries.
Program + Source files