If you are looking for Mac related info, please follow these links instead: Otherwise read on.
http://www.jamiegriffiths.com/kinect-into-isadora/
http://www.jamiegriffiths.com/kinect-with-isadora/
http://www.jamiegriffiths.com/new-kinect-into-syphon/
In early 2014 Apple bought Primesense*, and closed down OpenNI, reducing practically overnight the solutions for accessing the Kinect camera data. It is no longer possible to download the OpenNI framework so some of the solutions you will find across the web will not work unless you can find all the needed installation packages for OpenNI. Most webpage tutorials simply provided links to the now defunct OpenNi website.
(*Primesense were the company that developed the Kinect camera for Microsoft and the OpenNI framework required to access it on a computer)
On July 15 2014 the new Kinect for Windows 2 camera is being released to developers. At that point there will be many independent developers working to release apps that will be made available through a Windows Online App shop. But it will take a while for those solutions to filter down to the public. The camera itself is not being sold to the public till 2015.
OPEN NI VIRTUAL WEBCAM
OpenNi 2 Virtual Webcam Windows 7 & 8 and a thread on the Isadora forum
Version for Windows XP (no audio, unsupported)
Download and Install OpenNi 2 Virtual Webcam as instructed, set it up, and choose the source image.
Boot up Isadora and select the NIVirtual Cam as the video input in the Live Capture Settings window and click "Start Capture."
Note from Mark Coniglio: "One bug I noted: a couple of times when I quit the NIVirtual Cam, it was still running in the Task Manager and wouldn't start up again. I needed to use the Task Manager to end the process, and then things were normal again."
Note from another user: "sometimes, openNI virtual camera stops working"
FFGL
After July 31st Isadora v2.0 supports FreeFrameGL FFGL and so can potentially support this free plugin from the makers of Resolume. This may offer a kinect hacking option. Take a read of the following link.
http://vjfx.com/main/en/mmblog/mmblogintrinsicsrnd/item/3098-freeframe-depthcam-plugins-2
DELICODE NIMATE
Cost approx 200 Euros. Windows, Mac & Linux. Limited Demo Version.
OSC: The demo version will send OSC skeleton data into Isadora, after locking your Kinect camera serial number. NB You will not be able to use the camera again on a different computer with a demo version of Delicode NiMate. You will be required to buy the software.
SYPHON: The Syphon feed of the depth mapped camera image, is only available on a licensed version of the software.
SYNAPSE FOR WINDOWS
http://synapsekinect.tumblr.com/post/6698860570/windows-install-instructions
PROCESSING
Excellent resource page from Daniel Shiffman (Processing software), for figuring out how to do it yourself from scratch. But dependent on some OpenNi Downloads. Give it a try... if you feel up to writing some code.
DOIN' IT YOURSELF...
A tutorial on how to set up on Windows yourself... but dependent still on accessing the necessary OpenNI links.
http://www.codeproject.com/Articles/148251/How-to-Successfully-Install-Kinect-on-Windows-Open