This was originally created by Purvi Saraiya as a part of her master's work. It loads full-screen in a separate window in your browser and is no longer under active development. We will eventually fork it like some of the other visualizations on this site.
Unfortunately, this is not working properly at the moment. The progrm needs a file that describes the graph to be processed. That works fine when the applet is run locally, such as in an applet viewer (that's how the program was originally intended to work). But it doesn't work right in a web page. We need to fix this. In the meantime, try downloading the source if it looks promising to you.