Hardending Red Hat Linux, OS X, and Windows | The security folks at the NSA have online guides on how to secure Linux, OS X, and Windows operating systems. These are definitely worth a read of all articles even if an OS in question is not your main cup of tea. Here is the link: http://www.nsa.gov/ia/guidance/security_configuration_guides/operating_systems.shtml Page has been taken down This direct link
