A WikiWall is physical tool/technique to visualize the content of a WiKi. It was a started by RalfLippold and RainerWasserfuhr in late 2009:
http://farm4.static.flickr.com/3362/4642420601_4209c4097c.jpg
As of 2010 it consisted of 256 physical WikiWallCard's, that were placed on 16x16 grid with a ChessBoard-like coordinate system. Each WikiWallCard is backed by a WikiPage in the (JspWiki based) TeamWiki.

In an initial "RampUp" phase, the WikiWall was filled during extended BrainStorming sessions.
After the RampUp, only minor changes were made.
Replacing a WikiWallCard from the WikiWall had to be justified by pointing out the importance for the overall project.

During countless meetings with different people, the WikiWall was extensively used to point to hidden connections between various people, organizations, projects and concepts.

HomePage: http://noopolis.appspot.com/wikiwall