Wikiwhere is a tool meant to visualize relations between Wikipedia articles via links using directed graphs. It can both update relations on the fly and find the shortest path between any two articles.
Populate the first search box and click the search icon to visualize a single article and its relations/update the current graph.
Double click on any node to see what other articles are linked from that article.
Populate both the first and second search boxes and click the search in the second box to search for a route between two articles (might take some time).
Click a node to bring up a snippit of its article.
Click the clear button to clear the current visualization.