Windows Server 2008 has a new option when installing called Core.  The Core install is a very basic, cut down installation, which has a very minimal GUI. Well, it actually doesn’t have a GUI at all, just a command prompt, and that’s it. The advantage of this is none of your processing power is wasted on the GUI and your attack surface is reduced since there is very little surface. The Virtual PC guy has a guide here showing you how to install Windows Server 2008 Core under Virtual Server, Which is a very cool and handy thing to do. Check it out!