[Jakeman]

you can do this without using a hack. under the "User Titles" section of the control panel you can specify user title according to post count. you can fudge this a big and add an image along with the title or just the image alone. in the title field just put <img src="{imagesfolder}/image.gif"> and that image will now appear under a registered member's name if they have x number of posts. unfortunately this post ladder system only works with the regular 'Registered' user group right now... so if you wanted to do this with mods, admins, etc you would need to hack the code which i don't know how to do.