This plugin finds related posts and related images while you write your post. Pick related posts manually!
Related posts with thumbnails when the post is published
Widget - Related Images, Related Posts and the powerful search bar
WordPress admin new post page where Zemanta is suggesting relevant related images and related posts for the post you are writing.
List of related posts and a neat preview of the post you're about to link to
The email you receive when another Zemanta user uses your post as a related post