The Thermaltake Element Q Mini-ITX case measures just 13" x 8.7" x 5.1" but still manages to have space for a DVD/BluRay drive along with the rest of the required parts of your PC, though you are going to have a hard time using anything but onboard graphics.  The price is also small, $65 for a miniITX case is a great deal, especially when it looks as good as teh Element Q.  For any sort of SFF or HTPC project this case is a great way to start; as The Tech Report proves in their recent review.

"For just $65, Thermaltake’s Element Q Mini-ITX chassis offers a 200W PSU, support for 5.25" optical drives, and subtle styling reminiscent of the Golf GTI. We take a closer look to see if this really is the PC equivalent of a hot hatchback."

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CASES & COOLING