The Google Chart API lets you dynamically generate charts.
To see the Chart API in action, open up a browser window and copy the following URL into the address bar:
http://chart.apis.google.com/chart?cht=p3&chd=t:60,40&chs=250x100&chl=Chao|Tze
Press the Enter or Return key and - presto! - you should see the following image:
