It's easy...
Log on with you Main, invite a friend to your group...
Go to the place or the Instance, where the item drop, what you want... (with your friend)
Go out of game with ALT+F4 and log on with your ALT, say your friend, he shall invite you...
You see, your MAIN is still in GROUP but offline...
So, run to the place too, ALT+F4 out...
Log on with MAIN, kill all Mobs and ALT+F4 out...
Log on with your ALT and loot...
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I've only make this for ITEMS wich are BoP and Rar...
Perhaps you can use it for Questitems too...
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