If you have any questions about this, feel free to ask me in the comments.
This was the first PC I built, and it is designed to be a HTPC that is also for gaming and system emulation. It is definitely a more expensive build than most PCs but it is the most capable one that I can imagine.
This is the breakdown of the components that I used in this build:
Processor - Intel Core i5 3570K - 3.4 GHz overclocked to 4.2 GHz
Processor Cooler - Noctua NH-C14 (there is clearance for this to work in the case, although it is close)
Video Card - Gigabyte Nvidia Geforce 660 TI Overclocked
Case - Silverstone LC17B
Hard Drive - Seagate 2TB
Optical Drive - Asus BluRay Reader / DVD writer
RAM - Corsair Vengeance - 8GB Low Profile (Didn't mention this in the video but low profile RAM is probably a good idea, because you are trying to fit a lot in to a small case)
Motherboard - ASUS P8Z77-M
I give all credit for this config to SN3S over at http://forums.dolphin-emu.org/Thread-... because I loved the work he did on configuring and building his HTPC rig.