A: Windows Server 8 developer preview (now Windows Server 2012) had a Features On Demand installation option (see screen shot below).
This installation option installed a base Windows Server Core installation without all the other components copied to disk, creating a Windows Server installation with a very small footprint. This option was removed for the beta.
However, if you want this very small footprint server image, you could create your own by removing all the components of the OS you don't want (as documented in my FAQ "Q: Is it possible to remove components in Windows Server 2012?") and then capturing it as your own new base image.
To see more answers about Windows Server 2012, Windows 8, virtualization, and all things IT, click over to our FAQs page.