This is the fat-tree connection diagram for one of the cabinets of a CM-5. It was posted on a wall at one of the national labs in the US which had the pleasure of working with a CM-5 around the time War Games was in theatres. People still gushed about how nice that machine was to program 10-15 years later. SiCortex[1] tried to do something similar with their computers, unfortunately they failed and with them the last interesting connector architecture and the last interesting "supercomputer". even cray does linux now...