I bought this one:
and it works perfect and when I say perfect I mean perfect, no latency, multiple button presses, the works I believe its the same that another guy suggested, it MUST be ACTIVE.
and remember you MUST plug another old PS/2 keyboard for it to work. Do what I did, I ripped open an old keyboard and took the board only with the cable and wrapped with electrical black tape just for protection of the electronics and voila you have a working USB hotrod, believe its worth it since its the best joystick around period!!!