Macro Models in a Graph Representation

Geoff Wyatt, of the Heriot Watt University in the U.K., offers this site devoted to a non-traditional method of teaching interrelationships in economic macro models (it appears it could be extended to micro models). When I first saw it, I said, "Ah ha!" There is a brief description here, along with two chapters of a book that describes it. There is also a Java application for those who wish to try it on-line.