Couple of quick questions: how would the control boards/chipsets built into modern controllers like the DualShock/SixAxis even respond to control input from older controllers like the NegCon? Would the on-board controller even be able to recognize/parse the controller data sent to it?

Another thing, if you do get this going (which I would love to see happen since the Neggie's my best method for controlling Wipeout games): the game itself would need to be programmed to recognize that type of control input. I know HD registers D-Pad and analog stick control inputs, but does it recognize steering wheels or other similar NegCon style twisty controlling potentiometers?