SharePoint Security model

I have found some useful information related to SharePoint security from below links.

http://blogs.devhorizon.com/blogs/reza_on_blogging/archive/2007/03/12/457.aspx (How to break inheritance and create unique security model from object model, also see second part of current blog)

http://blogs.msdn.com/joelo/archive/2007/08/23/sharepoint-security-and-compliance-resources.aspx ( security improvement in MOSS, how to create security model for internet, intranet and extranet sharepoint site)

http://www.15seconds.com/issue/040511.htm (SharePoint and .NET security model)

http://www.sharepointsecurity.com/ (All about SharePoint security framework)