Consumable potions

Increase damage done,
Reduce damage taken,
Increased healing done,
Increases HP points,
Increases MP points,
Increases TP points,
Increases HP regen,
Increases MP regen,
Increases TP regen,
Increases tomestone currency gain,
Increases gil rewarded from duties,
Reduces gil require to repair gear,
Amulet of the phoenix (can be weared on top of your gear), when you receive fatal damage you instead gain the amount of damage times 10 as an absorption shield and for the following 30 seconds a single attack cannot reduce your HP below 1 - usable in ultimate,
...
The list is endless really.