Random Wiki Articles
Random Pages from the Superpower Wiki
Random Wikipedia Articles
Random Wikipedia Article within Category
Wikipedia has a Random page in category tool, which returns a random article or subcategory, but it doesn’t recurse. It can only find articles within the top level of the category. My little widget below does recurse. If it selects a subcategory, will enter that subcategory and then draw one of its members, and so on.
Here is a list of high-level Wikipedia categories for reference.