Microsoft Surface at Siggraph 2007, San Diego, CA, USA.
I like the fact where one of the spectators says, can you build it yourself? Where the presentator says something like, uhhhm well yeah but it wouldn't hold. This is more solid.
There is still a very noticeable latency as well, like one of the spectators states.
Where the presentator excuses with, Yess keep in mind that this is still a demonstration model. Yeah sure.
I also liked the fact that the presentator dragged images onto a phone, where one spectators asks something like, can we put an iphone there? and another person says yeah cool for itunes.
Where you hear the presentator "uuuhm yeah uhm nervous laugh".
Another concept which I thought was kinda cool educational wise is the Globe4d. The concept was there already for a while. Even won a price actually. But fun to see it back on Siggraph:
Too bad they don't zoom in on the actual hardware that is connected to it / below it on this video. Kinda fun, but not optimal opposed to real touch. Because you still interact with the image, even though your hands are not on the screen. So if you move your hands away from the screen, you still drag the image.