Unique item suggestion (in General)

I've heard a lot of complaints about rare items being not so rare. What if periodically a unique item was crated by our ever busy blacksmith and put up for auctions. A one-of-a-kind item that is TRUELY unique. Only one in existence with a kind of permanent naming on it.

I know people are going to come up with issues with this, but it would be way cool.

As long as it has no effect in game. Sure.

Otherwise, no way.

Unless you're fine with me getting an item that allows me to one shot anyone in the game, but the balance is there's only one of these in the game, and only I can have it. ;)

Did I mention balance?

The reason I did not mention balance is that it is obvious. If there is even a hint that an item might be unbalanced don;t create it.

A game I once played had unique items that were placed in game by the so called gods. These unique items could disappear at any time and be found at any time. Most of them had huge benefits but also huge penalties as well so only the most skilled players could reap the full benefits that these items provided.