ok so heres what i'm aiming for:
my cp will be able to play mame and xbox. theres 2 joysticks. 7 buttons each, 1 trackball, and a bunch of mame option buttons. for interfaces, i am gonna hack 2 madcatz xbox controllers for the joysticks and buttons and the trackball and mame options will be going through ipac/optipac. to switch between the option to either control mame/the computer or the xbox, i want to use 15pin male and female connectors coming from the madcatz's (for xbox) and ipac (for mame). the other gender would then be connecting to the joysticks and buttons.
another option is to just purchase a superbox10 with 2 xbox-to-usb ports from lik-sang(?). this might make it easier since i would only have disconnect/connect the madcatz to either the xbox or the computer depending on which i want to play.