Icons 
In order to spice up a message, a user can choose to assign a small graphical image (or Icon) to each post that he/she makes in the bulletin board. Icons assigned to the first posts in a thread are displayed next to the thread title in the forum threads list, like this:

Administrators can configure icons using a similar procedure to configuring avatars - such that you can add, upload, edit and remove them in the same way.
User Contributed Notes: Icons Add a Comment