I haven't come across that yet, so if any of you know, could you fill me in?
As for the discussion part, there are some systems I really hate and some that I think should work:
BAD IDEA:
1. First past the post. The "most dps wins the loot" system is utterly broken if you ask me. If multiple groups are all fighting the same world boss, then each of those groups should have a shot at some loot, some how. Doesn't matter how, but if you simply give all the loot to the highest DPS group, then you create two big problems:
Mega Guilds get to monopolize the best game content, and in fact have an incentive to do so. That frustrates a substantial number of your regular players.
DPS classes have advantages in races against single mobs. You don't want your high DPS characters to have auto-wins on the loot rights and other mob credits.