Datavisualization.ch is keeping a list of the tools that they “use to create interactive and dynamic data visualizations:”

That’s why we have put together a selection of tools that we use the most and that we enjoy working with. We called it selection.datavisualization.ch. It includes libraries for plotting data on maps, frameworks for creating charts, graphs and diagrams and tools to simplify the handling of data. Even if you’re not into programming, you’ll find applications that can be used without writing one single line of code. We will keep this list as a living repository and add / remove things as technology develops. We hope this will help you find the best tool for your next job.

I have mentioned many of these tools like ColorBrewer (many times), Processing, Processing.js, and Many Eyes.