The xbox 360 wired controller has a usb connector by default all ya have to do is download the official drivers from Microsoft, though Vista comes with the drivers built in.
I do have an Xbox Controller S that my brother modified for me, as the connector is internally the same as a USB, he swapped it wire for wire with a real USB connector.
It turns out that Gutsy has xbox controller drivers built in too, which is great for my Controller S, but i have to manually install drivers for my 360 Controller.
Now i can play 2 players in games, in both Windows and Ubuntu