This is the first time that I've seen these, some Scythe Slipstream "Slim" 120mm fans from Performance-PCs. Only 12mm thickness! These are critical as they will allow me to run an XSPC RX240 on the roof of the case as opposed to the much thinner Swiftech MCR 220 to give me much better cooling for the CPU, mosfet, RAM and chipset.
I'll run these in a push-pull config on both the top and bottom rads. Their CFM/decibel rating is so-so, but I'm willing to sacrifice that to give me more room inside the case. It is really, really tight in there with the two XSPC 240s, 5970s and the Zero-G chamber.