Steel Battalion controller for xbox.
end of story/end of contest
best game/controller you can buy: 40+ button, dual joystick controller with foot pedals.
http://www.ebgames.com/ebx/product/227919.asp
you can have a massive lan party/xbconnect war with up to 5vs5.
and if you're spoiling yourself, here's an available $500 cockpit for immersive gameplay:
http://www.popcultureshock.com/news.php?id=570
I rarely have time to play this game, but when I do, it's amazing.