In the last issue of ACM interactions, Lars Erik Holmquist mentions a very intriguing technology called u-texture:

Another laboratory at Keio SFC is run by Professor Hide Tokuda. This lab concentrates on the enabling technology for ubiquitous computing, such as operating systems and networks. One fascinating system is the u-Texture, a set of interlocking computational tiles that can be combined to create different applications. The tiles are roughly the size of a Tablet PC, have integrated network connections and of course RF-ID readers. They can be assembled in many different shapes and will automatically configure themselves to acknowledge the new connections. Fancy a new digital shelf, a smart table, or an electronic wall? Just put together a few u-texture blocks and you've got your new interactive furniture! I wonder if IKEA will catch on?

Some of the applications:

The AwareShelf can be created on a shelf-shaped u-Textures. When a user puts a real object such as a camera, a book, or a key on a u-Texture, it enables to browse information of the real object on the display on another u-Texture. The u-Textures have to be connected vertically to the u-Texture on that a thing is placed. (...) The Collaboration Table is a system that supports cooperative work with several participants by connecting u-Textures horizontally. Users can exchange and merge drawing data among connected u-Textures by drag-and-drop operations. (...) The ProjectionWall magnifies a connected u-Texture's small display onto a big one. It is effective for displaying a large picture that is too small to be shown on only one u-Texture. Data can be handled interactively by users with touch panels