When playing Modern Warfare 2, people like that get an instant mute.
Also, what bugs me about people like that, when things don't go their way they immediatly make accusations of cheating rather than admit that they are not as good as they think they are. Also, on the same subject, I really hate people that whinge on about "campers". God that bugs me. Esspecially when playing sabotage or demolition. The point is to set a bomb then stop others from defusing it. How is that possible without laying in wait for someone to come and try to defuse it? Whats the point in setting the bomb then walking away, leaving it as an easy target for the opposition? Also, in other game modes, whats wrong with finding a nice spot and sniping from it? If the game provides a sniper rifle, whats wrong with using it properly?