Share 'Slaving computers for Virtual Instruments.'

I'm at the stage now where I'm about to start using slave computers to store virtual instruments and control them via a LAN / Ethernet from my Mac G5 Quad.  What's the best way to slave them? What spec should they have? As this is a completely new area of expertise for me I thought I'd open it up to the floor here, as I'm sure there are many who slave on the forum. Cheers