[Zope] Zope Specific Example

Hi, I am trying to give a specific example of Zope server to demonstrate the power of Zope access control. I need a site that has lots of roles and permissions. I had a look at the Zope Powered sites in the http://www.zope.org/Resources/ZopePowered/ page but it does not really say much about the access control part. Any idea of a good example. Thanks in advance ~Meitham