One for the Mac-heads: I want to network iTunes but I’m not sure of the best way to do it. Anyone experimented with various options and found a solution?

This is what I want to do: I’ve got a powerbook upstairs and a Mac Mini under the telly, running Wi-Fi. I want to replace the wi-fi with powerline ethernet to get better performance (my house kills Wi-Fi very quickly) so there’ll be a Mac up here, Mac downstairs, Xbox 360 there too – and when I replace the powerbook, another Mac kicking around somewhere. Plan is to have them all connected via ethernet.

Each machine (Xbox excepted) will be running OS X and iTunes, and what I want to do is store the iTunes library in a single, central location (possibly an ethernet-aware hard disk). No matter what machine I use, I want to be able to use a single library – so I can update the iPod from whichever machine’s handy at the time, and so I can rip CDs from whatever machine is handy and then access the songs on any other Mac. What I *don’t* want to do is have an entire Mac running 24/7 or tunes streaming from one Mac to another.

Anyone tried something similar? Any top tips or warnings? I’m all electronic ears…