EDIT: Code was updated on 2/12/11
Magicka is $9.95 at Direct2Drive (D2D). If you use the 20% off code you can get the game for ~$8. If that code expires you can use the 15% code to get it for ~$8.50.
20% off code = EE4F47EE29EED0BC440C516E8BA278E8
15% off code = snowblows
The codes are valid on other games also.
Be sure to send this hot Magicka tip to your friends so they save money and we can all support a great Indy developer.
By the way, this can be activated on Steam!