I am not sure about the videos being fake or not, but I am pretty sure that it is possible if you´ve got the power of at least two cpus just for the image processing and at least two cameras with a high image quality and a high framerate. For me this is very exciting :P
I am just working on a project for my phsiycs class at school and will definatly try to put one of those videos in there as it fits very nicely to my theme :P
I am creating a simple touchscreen and some headtracking...

On the other hand I btw also like the idea of controlling games with your mind quite a bit :P

Anyway, it is just some very cool stuff I would love to play around with :P Or may create myself sooner or later...