Bought a Raspberry Pi and am trying that with Openelec, and that seems to work pretty well as a client. Quite a cheap solution.
Cheers Brian
You should also try the "new" rpi output plugin from here: http://www.vdr-portal.de/board18-vdr-hardware/board98-arm-co/120344-prototyp... It's a prototype now, but it works pretty stable for me.
István