The aptly named Cubitek HPTX-Tank is a whopping 230 x 600 x 610mm (9" x 23.6" x 24") and is specifically designed to hold the largest of system components, such as HPTX, EATX and CEB form factor motherboards.  You could put an mATX board in the case and probably house a small child in the spare area if you so desired.  It is about half the price of other large sized cases, such as the Lian Li PC-V2120 which will run you about $400 which leaves more budget for your oversized components.  Take a look over at TechPowerUp.

 

Yes that is a DVD at the bottom.

"Cubitek joins the ranks of Lian Li and Xigmatek with their HPTX-Tank chassis, which is one of three cases on the market capable of holding huge motherboards like the EVGA SR-2. With an unbelievable price tag for an Aluminum chassis, we take a close look to see if it manages to redefine the price / performance segment for such enclosures."

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CASES & COOLING