Two years ago I posted that famous Jeff Han multi-touch demo that became Microsoft Surface.
This amazing demo is similarly compelling - and I love that people are angry in the comments, always a good sign with new tech, things that take us way out of our comfort zone.
Beyond the fact that it's cheap (unlike Surface) and incredibly utilitarian here are four quick reasons why I think it matters:
1. Interactivity. The world isn't just about text and data - the idea that computing could move into a geo-spatial plane means that sculpture, music, cooking, dancing... just about anything that makes sense in three dimensions and less in two - can become digital. Projected onto surface or shape and interacted with. They called their talk the "sixth sense" which threw me for a second because of Bruce Willis and that kid - but I totally understand "the third dimension" - that changes the future for how we think about what could exist on our current screens.
2. Dexterity. We're meant to be losing a generation of kids (another?!) because they are trained to think in two dimensions and their muscle memory is focused on a keyboard, a console and a mouse. Yes that would be difficult. But the old can just feel old and the very young will be awesome at it.
3. Gaming. When you're projecting and interacting within that experience gaming gets a whole new box of toys. Proper interaction based gaming will make the wii feel like a wind up toy.
4. Mobility. Remember when monitors were nose cones? Now they're phone sized, which is just as annoying. Soon they'll be non-existent. You'll carry a fold-up paper, or just project onto your hand, or a wall or each other.
Anyway, I hope you have time to enjoy this - I think it will change the world - just like digital paper - eventually.