warning: this has not been tested on mobs
okay now,here's the scam
1) get a raid
2) tell your leader that you gotta leave for a few moments
3) when the boss is at 5% or something,leave the raid
4) if the boss drops something worth for it,then click on need,then,the raid will not see if you loot it, i did it with a box at AQ,but not sure if it's working on raid-rolling..
so here it is actually,hope this works. ill try to test it with my friends and will inform you if it works.
if you know if it works or not,then dont be shy to tell me : P