Google Charting API

How cool is this?

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 it:

http://chart.apis.google.com/chart?cht=lc&chs=200x125&chd=s:helloWorld

Press the Enter or Return key and - presto! - you should see the following image:

 

Very cool. In fact, just from reading the documentation, twiddling the URL, and using an IMG tag, here is a readymade graph for this post.

 

It's joke, in case you don't get it. [Originally from here]