This might be great for some type of whiteboard app.
If I need a whiteboard at work, I just plug in my phone to a projector and scribble w/e I want down. If I have a meeting later in the day I can just plug my phone into the projector in the conference room and can have my co workers instantly collaborate on my earlier notes. If I get home and feel like looking over or adding to my work notes, I can easily do so.
Of course the downfall to this whole idea is the fact that each location would need an available kinect and projector. I wonder how long until we can cram similar technologies into a phone though.