i recently modified a genesis and nes controller to work with a keyboard controller for a project i've been working on. i got bored yesterday and wrote up a tutorial.
this is a good option if your wanting to use genny or nes emulators on your pc with the original controllers and don't want to use the parallel port hacks. i also kept the wiring consistant with atari 2600, 7800 and sega master system controllers, so they should work as well.
tutorial can be found
herehere's a shot of what the connector port i made looks like installed(obviously the controllers look the same)
