Myth
Frontends (2) are motherboard+CPU+RAM (onboard everything) booting diskless.
Backend is a £99 Dell mini tower (special offer) with a PVR350 to record Sky over s-video and a DVB-S to get free satellite.
All have homemade IR rx.tx units (from the lirc site)
I have a 1.2Tb raid5 in there made up of 5 300Gb SATA drives.