Picked one of these up yesterday - and it's not just the regular controller, it also comes with the $20 usb wireless receiver so you can use it (and any other wireless 360 accessories like the wheel and headset) with your computer.
I have a Mac and the third party driver support for it is a little sketchy - but it works!
Maybe this warrants its own thread, but I'll just post it here:
Best Buy has the Blue PS2 controllers (official ones) for $20 as opposed to the regular $35. Price match = $18.50 (unless FS only matches with BB). Either way, still a good price.