Hello! I am hoping to be of some use to Wikipedia, however my coding techniques are not good yet, hence my lack of contribution. Must spend more time practicing. I made my first contribution in the Pro-Anorexia section after, honestly, coming across it and getting pissed off at the blatant advertising a specific site was making on it. I didn't believe it was ethical to have such sites linked so directly when they cause far much more harm than good.
The CategoryTree is a MediaWiki extension that provides a dynamic view: you can change how much you see of a category's structure as a tree. You can use it to show a category and its subcategories by putting the category name between category tree tags like this:
<categorytree>
Trees in religion
</categorytree>
The result is a category tree like the one shown to the right. Click on the triangles to expand and collapse the tree.