Final Fantasy 14 communities have been in a bit of a commotion lately—as a recent mod stepping into the limelight has exposed a vulnerability in the way Square Enix has handled its new-and-'improved' blacklist feature.
In essence, this solution to the game's stalker problem has inadvertently made it very easy for ToS-violating (but currently untraceable) players to uncover all of their target's alternate characters.
A fuller explanation requires context. Firstly, while mods in Final Fantasy 14 are against the terms of service, a ton of players use 'em anyway.
This is because Square, at present, operates on a sort of 'don't be an idiot' policy. The official stance is that mods are forbidden and you should not use them under any circumstances.
Under the table, however, Square has stated that it can't spy on your computer to see what you're using. Instead, it will simply punish you if you're either obviously cheating, which is detectable through common sense, or if you're reported for it.