still would like to point out i count 64 drives in the bottom,
now onto some basics, i'm not certain if he used this method, but one can using cheap 2 port controllers with (port multiplier support), run a multiplier off each port end up effectivly getting a 10 port controller for ~ $120, being there pcie 1x slots most of them, chuck a few of them in a board like a GA-880G-UD3H and you could very easily have yourself a 50 port NAS, running off a single motherboard, chuck in some 2TB samsung f4egs (because they are cheap where i am) and you could well have 0.1PB of usable space for i believe in USD, $6400. however thats excluding redundancy, but you would still have the option.