I bought a Microsoft XBox 360 controller with the intention of having a console quality gamepad on my PC and Mac. Thus, knowing that it only come with Microsoft drivers, which only supported rumble using the Xinput API which no games seem to support yet, I also had the intention of finding out how it works to create my own DirectInput/MacOS X drivers.
Just before Christmas 2005 I spent about a week looking into the USB reports sent and received by the controller, so as to understand the readings from the buttons and axis, how to control the LED and the rumble motors.
After I discovered the means to control the LED and rumble motors the people at Free60.org updated their gamepad page with my findings, which was then inserted into an updated driver for the original XBox controller.
After making these findings I implemented a driver for MacOS X. It can be [OsxDriver found here].
Then, in January 2007, it turned out the Microsoft Wireless Gaming Receiver for Windows was out. I went down to a local electronics store to pick one up, specifically with the intention of making it work on MacOS X. After some investigation it seemed fairly straight forward, and so implementation of the driver proceeded.