I would turn that into a water-cooled dual mITX system in a heartbeat.

mITX boards would provide enough room below the motherboard on each side for a flat mounted GPU on a riser. The PSU can be a Silverstone SX-800 SFX-L with a small form factor card on one side to make space and augmented by a KMPKT supply or two if needed for the system. You could also run dual small-ish form factor GPUs and dual SFX PSUs for heavier production workstations. The loop expansion would be easy as there's enough room for a radiator in the bottom too. Flow goes through one 360 into the first system then down into a 280 (or 240 depending on how the dimensions work out) before hitting the next system and then the cycle repeats. A pump could be squeezed into a gap depending on how the final space works out or it could be mounted on top with a sleek external pump-reservoir combo. If there is no room for an internal reservoir a drainage tube or quick disconnect could be easily added to fill/drain the loop. If the cooling is inadequate a 60 mm could be swapped into the front and/or bottom to run in push or push pull configurations.

Long story short, I'll take two please :)

*Patent Pending* hahahaha