Player :Marantz NA7004 mod
Controller : IPAD + Plugplayer
Server : PC NAS. ATOM base is enough. But recommend 1000 base-T NIC.
POS:
PC as streaming audio device
Marantz as player.
Con:
You need to always power on the PC. Therefore, you need to build a low power PC system, like AMD Fusion motherboard platform (I will get one free soon!!!) Only 8W TDP.