Hey,
Looking for a sub $500 htpc/media PC thinking will need at least 2x PCI E
1x HDTV Tuner
1x WLAN Card
Thinking would want a sorta decent CPU and ability to stock with RAM as considering using it as a multi function box with ability to play 4.4 GB Bluray rips.
take a look at this website, they build a small but powerful PC
http://au.shuttle.com/
Good luck!