I'm glad Lowlander gets what I'm saying.
Rovingcowboy is obviously not following my idea.
Simply, raspberry pi is a bare bones ARMv7 driven PCB which boots from an SD card to a linux environment. It is very bare bones, very quiet as there are no fans and reasonably fast for small projects etc. It can be housed in a small case the size of a credit card (ish) and about an inch deep. Some of the commercial cases will fit to the VESA stand connectors on the back of a TV or PC monitor making for what could be a very minimal footprint music center. Rovingcowboy - check them out on the internet as it seems you don't know what they are/do.
As lowlander understands, the music itself is stored on a NAS drive, not the SD card of the Pi. My current setup is serveral windows PCs running mediamonkey with the mediamonkey database ("MM.DB") shared between them (stored on the NAS drive too) - thereby any additions or changes I make on one PC will be reflected on any of the other PCs as they are all running from the same shared database. It also means I only need one repository for all my music files instead of multiple copies on each PC. What I would like to do is run several raspberry Pi's in the same way.
Surely that's easy enough to understand.
The reason I mentioned about the live CD for windows or a small bootable partition install is because unfortunatley mediamonkey is not yet available for Linux, but the aforementioned would speed booting to mediamonkey on a windows PC considerably.