Imo all legendarys should work like a heirloom 1-90, since its so hard to obtain, with exception of cloak. Maybe that one unlocks after WOD launches so it can be sent to other toons.
Direct links to those legendary items:
Legendary cloak
Dragonwrath, Tarecgosa's Rest
Sulfuras, Hand of Ragnaros
Thunderfury, Blessed Blade of the Windseeker
Warglaive of Azzinoth & Warglaive of Azzinoth
Shadowmourne
Thori'dal, the Stars' Fury
Val'anyr, Hammer of Ancient Kings
Discuss, what do you think?
I think it would be awsome to be able to use my Thunderfury 1-90(100)