Casting spells in Rage - DragonMag Item

[TC X0 Lt 0X]

I remember at one point or another a discussion or mention of an item in an issue of Dragon Magazine which allowed barbarians to cast spells, use concentration, and other things normally restricted in a rage.
I not sure the name of the item, but I definitely remember its existence.

Does anyone know the name of this item and which issue it appears in?

[Maat Mons]

The rage casting feat (Dragon 310, p30) lets you cast swift- and immediate-action spells in rage. 

[TC X0 Lt 0X]

Update

From what I am told, the item is called the Torc of Tranquil Fury.
Still not sure what magazine it is in, but perhaps this will jog someone's memory.