I wasn't aware what it was, and while I could have asked the person by PM I thought I would ask here in case others were interested.
Veks' answer doesn't imply its a moderator tool. From what he says it implies its due to me, since I moderate certain game boards. Unless I have completely misunderstood the use of 'you' in your post Veks?
And if a moderator is watching me I have no issue at all with that, nor of others being aware that they are. I find it quite comforting actually!