This tech demo by MIT graduate David Merrill is really astounding.
More, is a perfect example of playful interaction design. His Siftables are tiny blocks with a small screen aware of their position and surroundings, capable to communicate between them and with external devices. The result is a lovely user interface for Lego nostalgics, which opens a lot of interesting possibilities.

Great idea. Kudos.

[Thanks Gianluca for sharing this on FriendFeed]