Yet another great Google API for the masses, on the fly charts. You can simply use a URL and set of parameters to describe your chart and the output is an image file. So, use the url in your blog post or place it in your href tage and get a great looking chart in a snap.
Down side, there arent as many options as I would like through the API URL; I cant show perentages on te pie chart. Put they look great, they are easy to use and you can update them on te fly simply by changing the URL.
Check out more information on this cool little feature at http://code.google.com/apis/chart/
or try one of these examples: Pie Chart, Bar Chart, and even a QR Code.