This is the very beginning of the development of the Multibot3d. This five extruder model could print in cyan, magenta, yellow, black and white. Multimaterials could be used. It could be made with a larger circle and accommodate six, seven, eight, to infinite numbers of extruders.
So far, thoughts of integrating a Smoothie v2 board to drive five extruders are being developed. Collaborators are being sought.