very cool...a good first step in the direction of display revolution.
as far as expose, I'm looking forward to the time that I can establish a wireless connection between my cerebrum and my computer, so that I can think about triggering expose and it triggers.
or I can just move my window in my head.
Of course, there's a lot of "background noise" to thinking, and a lot of inadvertent thinking just because your subconscious wants to screw around with you. I could imagine windows flying all over the place, important documents getting deleted, etc., just because you didn't want it to happen.
I guess, then, you'd need a high threshold--you'd have to be thinking really hard about something to make it happen. I don't know how useful that would be, but it would be cool as all. Even cooler than these 3D displays (like how I segued back so that anyone who reads the beginning and end of my post won't think that I got horribly, horrifically off topic, even though I did?).