Most wiki-based documentation I have worked with has sooner or later turned into a tangled mess of outdated information. Some pages are maintained actively while others aren't updated anymore and you never know how reliable the information still is. For a while I've been thinking about a simple technical solution to this problem. Here it is.

My general assumption is that new information is more reliable than old information. That means, a page that has been changed yesterday has a higher chance of being relevant than a page last changed five years ago. The idea isn't particularly new: It's a bit similar to what Eclipse Mylyn does for Java developers.

A wiki is a graph consisting of pages connected via links. Using age information, you could highlight the subgraph that is most active in respect to changes. Links that lead to newer pages are displayed in a lighter color while links to older pages are displayed in darker colors. Page titles could be color-coded in the same way. Users always know if they're in the active center of a wiki or in a rarely updated, possibly outdated area. You can always push pages into the center by making a trivial edit.

Taking the idea one step further, with a little bit more effort a rating system could be implemented. The system could take implicit parameters like age information or page impressions and explicit parameters like user ratings into account. For each page, a score could be calculated that is used for color-coding of links and page titles.