My cousin was tired of having to use his brother's crappy Macbook Pro to play PC games. He was mainly a PS3 gamer, but he just can't get enough of strategy games, which are mainly only available on PC. After suffering another 8 months of using the Macbook Pro, he finally caved. I drew up this list a week ago, and then started grabbing parts over the weekend. I completed the build a couple days later once I got all the parts together.
His bedroom is fairly small, so a good miniITX build was naturally the best fit for that environment. This was my first foray into building a small-form factor PC, so I was glad to to have the opportunity to gain some experience with them.
Added on July 8th, 2014
Upgraded the Sapphire Radeon HD 7770 Ghz Edition to an ASUS Radeon HD R9 270. Significant increase in performance was gained.