Diskless Nano Server (PXE Boot)
Given how small Nano Server is, it could potentially fully fit in RAM allowing diskless scenarios (boot over PXE) where a small chunk of system persistent data (i.e. Certificate Store, local secrets, logs, etc.) can be stored on a remote VHDX accessed over the network. That could make the OS run faster and become more resilient to system storage issues. Also it could allow moving the OS instance from one server to another (by reassigning the boot image to another MAC on PXE), in case of a hardware failure.
Daniel Sutton commented
Can see this happening. Would allow HyperV hosts to be disk free like VMware.
Rich Siegel commented
this is what citrix pvs does...