Since MP servers have been recently attacked by griefers who destroyed, cheated and made con art to make people grieve, I had an idea. I'm not sure if this has been used, but there should be a plugin where you can determine the coordinates of a player, what town they are in (needs towny or a plugin like that), what biome, how many blocks away from the spawn point, and the direction they're facing. Only operators can use these commands. It will message all ops when a hack is detected, by who is using it and what it is.