I imagine it is some secret moderator thing.
I use something similar that is only visible to moderators or administrators for "problematic" or "Totally awesome" users that the group can keep an eye on. With the selected icon, I can spot posts by "flagged" users to help gain or take away credibility, I also have specific icons show up for posters tend to post in more helpful forums, as opposed to "off topic". And lastly, if they end up posting many times per day (currently set at 25 posts), they will also get a special icon that looks like a SPAM brick

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It adds to the fun of being a moderator and administrator on that site

. They also come in handy, but it took allot of coding in PHP (something I am quite bad at)

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And no, this isn't on my site, as our forums are quite dead. It is for a car site that I wish to remain anonymous as being a moderator / admin for

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