plugin req.....

i would like to know if it would be possible for someone to make a plugin that would make url and/or image not show up if they have not posted in a thread a way if you want to force participation in a forum cuz i intend to start a texture and texture package download forum but i dont want user to just register and take everything without an effort
if this should be in the mod section please move it as i dont know if this would be one or a plugin