The web part pie chart from the demo was created by Paul Grenier and is part of our live online workshop solutions. Unless Paul releases the code to the public, you’ll have to take his workshop

Regarding documentation for the Yahoo API, here’s a pointer to the resources you need to create your own charts and graphs:
http://developer.yahoo.com/yui/charts/

In your recorded presentation you mentioned that you have all kinds of documentation to implement yahoo based charts on the website. I searched the site for this, was able to find the google api code but not the one with yahoo and linking the list view. Would appreciate if you can point me to the link and webpart Pie_Charts.dwp you used in your demo.

Thanks,
Varma