Many Eyes is a cool site that can produce visualizations of various types. You can upload your own data and publish the visualization on their site.

Internet usage visualization on Many Eyes

Many Eyes is run by Visual Communication Lab at IBM. It seeks to “democratize visualization and to enable a new social kind of data analysis.”

Note: I couldn’t get Firefox to view visualizations even though I have the latest Java plugin and Java normally works for it, so I had to view them using Safari.