Personal Recommendations
The {!ctf} extension on this wiki puts Personal Recommendations at the bottom of each user page.
Here's a user page. At the bottom is that user's Personal Recommendations. When you're logged in, you can access your page by clicking on your name (top right).
Like Related Pages and What's Popular, these recommendations come automatically from other users as they move about on the wiki - i.e. they're a form of collaborative filtering or co-learning.
Personal Recommendations shows a user stuff they haven't seen yet but is likely to be relevant to them, at least according to the rest of the community moving about in their immediate vicinity. This is a powerful way to share tacit knowledge and is often the most efficient way to spread information.