Creating a blog entry about a course or an activity will create a link to that activity / course in the blog. The icon that goes with the link is (I feel) quite big at the moment and would look nicer if it was a bit smaller.

Replication steps

1. Create a course.
2. Add activities.
3. Enter the activity and add the Blog menu block.
4. Click on the link to 'Add an entry about this activity'.
5. Add some content.
6. Click 'View all entries about this activity'
7. At the bottom of the post should be associated link and the icon I am talking about.