Razorfish, a group dedicated to creating innovative and effective solutions focused solely on "emerging experiences and technologies", have ported their DaVinci Physics Illustrator to Kinect. The application was originally created to take advantage of Microsoft Surface. Rather than using multi-touch, as originally intended, gestures are used to directly create and interact with objects on screen. Users are able to grab objects on screen and move them around the environment, controlling the physics. A video demonstrating the application can be found here.
This is one of many pieces of software the open source community have created for Kinect since the device was "hacked" shortly after launch. Since, developers have been controlling hand puppets, browsing the web and hunting Arnold Schwarzenegger. And again. It's early days, and there is much more to come from open source software, we'll make sure to keep you up to date!