For a limited time, the Kinect Adapter will be available free to customers who have an existing Xbox One console, an Xbox One Kinect Sensor, and an Xbox One S console. You will need the serial number of all three devices. To request the free Kinect Adapter, contact Xbox Support Australia. Enjoy :)
Found via HUKD
Grabbed mine a month ago when the 2TB model came out. Was pretty simple to do, although the Kinect now needs mains power which is kind of disappointing.