Generate 'Pie chart' graphics with PHP?

[kapow]

Is it possible to generate 'Pie chart' graphics with PHP?

I have a site that stores users answers to questions, in a database. I would like to be able to show the answers graphically e.g.
Very good = 60% ¦ Good = 10% ¦ Fair = 15% ¦ Bad = 10% ¦ Very bad = 5%
Represented as a Pie chart, or bar chart (nice to have a choice).
So can PHP generate images. I believe GIFs are proprietory and PNGs are open source. I am happy with PNGs - or any other ideas.

[bcolflesh]

JpGraph:

[aditus.nu...]

[surfin2u]

Search on google for php class pie chart graph