you can even use a standard Xbox controller if you can make your own USB-Xbox adapter plug. the drivers for the non-360 xbox controllers can be found online, as well as a program that you can edit the controls.
and yes, i use it for my Sega Genesis emulator (Gens+) and its awesome. it also works in all my FPS and racing games.
You can hook up your computer to your x box. Its made to be networked together, its microsoft. Then you can listen to music off your computer and stuff. If you have a network (router, wireless or otherwise) you hook them both up, go to the setup screen of your x box and go to "add computer to network" or something like that. You can search for the drivers on line so your computer will reconize them.