Key Items... (Do you need it?)

[Rydin]

I'm in a thread starting mood today...

Anyway... this is a really simple one...

In previous FF titles, you get a random pointless item from some chest somewhere or some boss. You think to yourself, "What the hell is this?"

So you open your inventory, and lo and behold, the item isn't there... /sadface
but then /epiphany!!!!! You check your key items and there is that seemingly useless item. The description is vague like "A bottle of some kind..." or "Wonder what this key goes to?" or even "A crumpled dirty note..."

And you're like "SE, could you be more cryptic"

But you press on...

3 towns later, you meet some old lady sweeping her porch and she mentions dropping a key to her cellar. Without the key, she can't go down and feed her pet kitty. You whip out your key item and triumphantly say "You mean THIS KEY?"
She is ecstatic... grabs the key, opens the door and promptly runs screaming. You realize the little kitty has been feeding on venom rats or some such thing and has grown into a vicious Boss coeurl. You kill it and receive some epic prize

Or some old hermit mentions he hasn't seen his wife for years and the "Crumpled Dirty Note..." turns out to be her failed attempt at sending him a letter before she passed away. He is moved by this and allows you to gain access to some labyrinth maze dungeon under his house.

I want this. I want seemingly innocuous key item that proves to be of great importance later on in the game. (Could I have just said that instead of going on some long spiel about old ladies and hermits? Maybe... but would you really have wanted me to?)