Wikidsmart turns Confluence into a semantic wiki (http://en.wikipedia.org/wiki/Semantic_wiki) so that you may contextually capture information in a structured way. Here's a bit more about it:
http://www.zagile.com/products/project- … wikidsmart

plus you can see an example in action with this video, contextually integrating with Jira:
http://www.zagile.com/products/Semantic … ility.html

We will have an example up soon of semantic search too but here's a rough version on youtube:
http://www.youtube.com/watch?v=jtQJxxgkq3o

Also, it's open source so you can download and use it free, just plug into Confluence. And it integrates with Jira, Subversion, Perforce, etc. in a very deep, contextual way.