The Nyko Zoom is a great idea. It’s basically a lens set that sits over your Kinect that reduces the space the Kinect needs to sense you in three dimensions. That way you can feasibly stand just a few feet from the Kinect and do all your running and jumping without fear of falling into furniture.
Specifically, the device reduces the necessary space needed to play Kinect by 40%. We tested it, above, and it worked quite well, sensing us in positions that would normally be impossible in a regular room. It costs $29 – a bit pricey for a piece of plastic – but if you live in a small, cramped apartment it may be a great solution for increased Kinect play.