A recent Wired article highlights the use of the Kinect as a terrain imaging tool, to capture data for anything from glaciers to asteroids.
According to Tedesco, one of the scientists mentioned in the article, the Kinect works as a much more affordable way to capture the kind of data they need. It also helps inspire students to do related research because the Kinect is a tool that they're likely already familiar with, and doesn't seem as imposing as more complicated imaging equipment.
Read more about their use of the Kinect here.