FOSS gamedev and creative worlds

I was sitting at my PC with my brother at my side one morning, really wishing that multiplayer was possible. Yes, you can play with different machines, but that's a real waste of multi-core machines when I could just utilize multiple instances using different gamepads.

Does anybody know of any open source code that adds gamepad support to a similar game, and does anybody know how much effort it would take to merge?

This old topic has some code for retrieving input from a joystick/gamepad. For now, one can use QJoyPad on linux for multiplayer.