XTools
Wikipedia
Golden
The Golden Research Engine is a comprehensive factual data discovery tool that helps to research and track information on millions of topics and entites.
Wiki Rider
Six Degrees of Wikipedia
Find the shortest path between any two Wikipedia articles. Traverse hyperlinks on Wikipedia to find the least number of clicks it takes to navigate between any of the nearly six million pages on the world's largest free online encyclopedia.
Wikiscan
Wikiscan is an independent statistics site on Wikipedia and other wikis hosted by Wikimedia Foundation. It was created in 2011 on the initiative of a voluntary user.