In June, Microsoft started selling the Xbox One without Kinect. In October, you'll be able to buy the Kinect on its own—but it'll cost you $150.
Standalone versions of the Xbox One's Kinect will go on sale October 7, Microsoft said today. The motion-sensing accessory will come with a digital copy of Harmonix's Dance Central Spotlight.
So the full breakdown:
Xbox One without Kinect: $400
Xbox One with Kinect: $500
Stand-alone Kinect: $150