One of the things this website gets a lot of traffic for is an Adobe AIR Native Extension I had made a few years back called JoyQuery (if you must have the old version, it is still available here). Since then I have been working in my spare time, which fluctuates in and out of existence, to create an updated version that is more powerful, more efficient, and has a more elegant API.
This new version, with a new name AIRControl, will be completely open-source (except for the Adobe AIR code libraries from the AIR SDK I cannot legally distribute), and be compatible with both Windows and, for the first time, Mac OS X. The project is currently hosted on my AIRControl GitHub repository.
I am nearly complete with this release. I have finalized the C++ code to interface with the game controllers, built the native libraries, and tested them; and they are running beautifully. Now I am currently in the process of writing the ActionScript side of the library, to expose all the wonderful new features of the native libraries to your projects. With all of the hard parts finally out of the way, I expect this release to be finished no later than this weekend!