We're just starting out on a project which has a tremendous amount of "Data Visualization". Here's a first experiment with using Gapmider charting tool. It requires setting up a Google Spreadsheet with your data, and using "Google Gadgets" to generate the motion charts. See this stepwise guide to setting up Google Spreadsheet with Gapminder.
Here's a chart based on some experimental data that we entered in a Google Spreadsheet:
Gapminder is path-breaking data visualization tool built originally by Prof Hans Rosling, a visionary proffessor of "International Health" at a Swedish University. Later, Google bought the Gapminder technology, and released its API. See the Google Visualization API Reference and an implementation of the same at https://developers.google.com/chart/.
See this incredible representation of how increasing GDP of India and China over the years has changed indices like "Infant mortality" and "Population increase", and how this compares with EU, and USA -- all in one chart.
There is a project in Drupal http://drupal.org/project/gvs for integration the Google Visualization API reference with Drupal. This should do the job of integration with Drupal.