Some years back, 2003/04, when I was playing Call of Duty (the original) with my two brothers. We played on the same server all the time (some clan-server) and we were always number 1, 2 and 3 on the scores. They could see that we played together, because we had some [] tag of some sort. Quick side note: This is probably the only FPS I've ever been truly good at, playing, mostly as a sniper, with something around 50 kills per death or something. So one day after a couple of weeks playing on the server, one of the clan members suddenly wrote, while we were playing, that we were disturbing the servers quality and their overall experience with the game we cheated (which we did not), and then we were kicked and could not log back in on the server again.