Nice build. Looks about the same size as my little Acer 1920. I picked it up for $50 on ebay (no hard drive or OS included), cribbed some parts from other PCs, and plugged in my Ceton InfiniTV 4. I just had to add an extra fan to keep the Ceton cool. I have the same Sandisk SSD as you too. It's been working great. Much more reliable than my old OCZ. I have a 3TB drive and only 4GB RAM, plus an Ortek IR dongle. My system is nowhere near as nice as yours but it does fine for HTPC purposes and would be great for someone on a tight budget. And it's really quiet too.
One neat thing I did was plug a couple of extra USB ports into the MB, leaving them on the inside and plugging in the unifying receiver for my Logitech K400. That leaves all my external USB ports free.