Magic Costs

In my last post, I talked a little about magic. One of the things mentioned is that magic needs to have limits. One way to limit magic is making it cost something. You basically need to make an economy for the magic. So I compiled a list of costs that might be involved to use magic. It is by no means exhaustive, and if you have any other ideas, please comment.
The following are ideas that can be used as 'magic currency' and put a limit on the power of a magic user:
Mana, mp, mental energy
Physical energy (makes you tired)
Blood
Water
Rare ingredients (eye of newt, etc)
Sacrifice person, animal, body part, etc
Heat
Ingested metal (Mistborn series)
Color (Warbreaker)
Concentration
Memorization
Time
Strength
Age
Hunger
Electricity (technology)
Ammo (like guns)
Losing a sense (like sight)
Available only under certain circumstances (midsummer's eve, after liking this blog, etc)
Complex rite performed or symbol made
Making calculations
Dancing or singing
Using a special artifact (sword, wand, etc)
Faithfulness to a god or demon
Powerful emotions
Cards, dice, or luck
Lifeforce of an animal or person
Adherence to a strict code
Horoscopes
Having a likeness connected to an object or person (voodoo)
Literal money
Using a special language
And the list could go on and on. Any other costs you can think of, please comment. The more creative, the better. Magic doesn't always have to be portrayed as some old man reciting from a dusty tome.

Reblogged from http://sageeyesblog.wordpress.com/2013/01/21/magic-costs/