Intrael is a server that provides an HTTP interface for the MS kinect.
This article functions as an introduction to building OpenKinect and as3kinect projects.
I have been experimenting of late with the Xbox Kinect as a cheap Mocap source to generate BioVision Hierarchy (BVH) files for upload into Second Life, and the results are pretty encouraging.
This page lists the people currently involved in the OpenKinect community and development effort. If you're starting a new project or working on a particular new feature, check here to make sure someone else isn't already working on it!