This one looked interesting. (Apologies for the poor quality and abrupt end.)
Physical tiles allow you to define and interact with a play area. Placing a tile expands your play area to cover that tile. Drawing various pieces of information on the tiles enables you define the tile's purpose and characteristics.
I like the idea of using the tiles to act as windows into a larger virtual play space. The ability to modify cards, e.g. drawing in the firing direction for a cannon, was neat.
Drawing on the tiles is supposed to enable you to carry around a small number of cards to play the game. Of course an alternative solution would be to enable the player to soft-assign roles and characteristics to the tile via the AR interface.
Framerate was acceptable (on a Nokia N95 using Studierstube tracking library.
Duy Nguyen Ta Huynh, Karthik Raveebdran, Xu Yan, Blair MacIntyre (Georgia Institute of Technology), ISMAR 08.