I think for anyone contemplating really getting into hifh streaming there are two fantastic options out there right now for a server:
Free: Daphile. Built on the excellent LMS, it really is great software but I believe needs dedicated hardware, i.e. cannot set on your nas. could be wrong.
Not Free: Roon. Great software and a tweakers dream, can live on server side software including popular nases, windows, mac and linux.
For streamers the list of options is literally endless by now, it can be so many things particuarly if you have a USB dac, but certainly Raspberry pis are a great start. Sevenoaks wont want you buying that because its only a few quid and besides get it on amazon.
There is amazing kit on ebay as well, just think fanless PCs
I got one of these for instance:
http://rover.ebay.com/rover/1/710-5...0001&campid=5338728743&icep_item=254576328849
Install roon rock on it and it can behave as just the streaming section of roon. It has no fans and you'll want a power supply bringing the cost to like 80 quid tops. USB into your dac and you have a streaming solution. Or you can use the two above in tandem, i.e. install daphile on the fanless PC and have roon control it as an endpoint.
So many cool options out there for peanuts.