Arena Quest-

Scythe of the Void

Heartseeker

Sword of Wrath-

I got this great sword from killing a world event group of monsters that had a named creature in it, I believe they were undead.

Impenetrable Cuirass-

I've gotten this one twice, once from a quest reward once from a drop.

Heart of the Glacier -

I got this one last time i killed Vertar.

Curgen's Hammer -

Master Quest item.

Cloak of the Night - 

Quest Reward

I'm sure there's others i'm just interested in what people have found in their playthroughs.