Uses include a live translator of italians and traffic cops, and that's it's really. Oh and maybe sign language too.

I like the idea of everybody shining IR lasers all over CCTV though! Finally I get the 'thousand points of light' goodness.

Microsoft is not doing something new for now. You should have a look at: http://www.ted.com/talks/pattie_maes_demos_the_sixth_sense.html