If I personnaly think I can do better without them and they refuse to quit of their own accord, then I'll put a bullet in their brain until they are so miserable they rage quit. Or if they have offended me over xbox live like say on Halo, where all the 10 year olds play and the power levellers are who think they are the greatest player to ever pick up the game, I'll wait for them to take damage, then snipe them. They die, I kill them, but since the enemy does damge, they get the kill. The ultimate GTFO ASSHOLE strategy.