Many people seem to think this it is possible, yet clearly in this document the boundary is stated as inter-process which to my mind means “no network”.
Another document is completely unambiguous:
The named pipe transport has very little reach; it can only connect to services running on the same machine
So why are so many posters here saying it can work?
I think you need to make a distinction between Named Pipe and WCF binding implementation NETNamedPipeBinding.
The NetNamedPipeBinding is a predefined binding for WCF for on-machine communication.
But if you check the MSDN documentation about Named Pipes, you can see that it is possible to setup a named pipe across network.