Alternative Magic Systems

[JoshuaZ]

Non-Renewable Pay Per Spell
Mechanism: Like Pay Per Spell, only the resource you're paying with isn't something innate to your character that comes back when you rest. Instead, you're paying with a meaningful amount of in-character money; or permanently aging your character, bringing her one step closer to inevitable death by old age; or things like that.
Used by: Many. Presumably the Mistborn RPG, if it ever comes out. I forget which popular game uses the aging mechanic as its major balancing factor. Ars Magica, maybe?
In d20: I guess this is used a little bit, with component costs (especially for 4e Rituals). 2e and earlier even had the aging thing for certain spells. But these things could be drastically expanded. Doing so seems to be against the mainstream "feel" that D&D magic reaches for, though.

Well also xp costs are sort of life this. I've seen people try to make completely xp based casting systems for d20 and have yet to see one that was reasonably balanced. It is quite hard to do. Regarding Mistborn, I'm not sure what you are talking about. Do you mean the feruchemy? That only requires storing up traits, you still have the total amount at the end.