I've been wondering on this case... it might be possible to run an SLI setup where the main card is traditionally seated in the mobo, but the second card can be stood up using the PCIe extender.... the only issue is if both cards are any of the Geforce GTX 10x0 models, I will need to run a HB bridge...
This will not work for a 90 degree ofset between cards... really whish Nvidia would support a flexible HB bridge design
EDIT: O well, seems I'll be sticking to the Evolv ATX Tempered Glass case then...