I'm basing my HTPC design off of Anandtech's recent sub $800 PC guide. I'm basing it off of the Intel HTPC one...'cept with 8 gigs of ram and two 1TB hard drives it comes out to be about grand. The gigabyte motherboard (w/ NVIDIA 9400 gfx) plus 2.5 ghz Dual Core seems to be a great combo.

Denon 3808, M22s, M2s, VP100, Hsu sub