Previously published in the July issue of TechNet Magazine, these are two PDFs of Windows 2008: Operating System components and Active Directory components. The posters explain how they work and detail capabilities. They are great resources to have up on your office wall (you will need a big printer though).
The Feature Components poster highlights the following components of the Windows Server 2008 operating system:
Network Access Protection
Windows Server Virtualization
The Active Directory Poster highlights the following components of Active Directory in Win2008
AD Lightweight Directory Services
AD Federation Services
AD Rights Management Services
AD Read-Only Domain Controllers
These are painstakingly created by two Microsoft employees in Australia, Martin and Astrid McClean. These two have been building these posters for years and they have all been great hits, usually causing multiple re-printings.