Seriously, this has to be the coolest thing I have ever heard and it may make me buy an iPod:
Square Enix Announces, Releases Song Summoner For iPod

Game Features
- Transform your iPod songs into "Tune Troopers" to combat the evil Mechanical Militia.
- Tune Trooper types and abilities are determined by the songs used to create them.
- Your Tune Troopers can be powered up even outside of the game—just by listening to the songs you used to create them!
- Control Ziggy, a "Conductor" that creates warriors out of music, and guide him through his journey to save his brother Zero from the Mechanical Militia.
- Experience a turn-based tactics battle system, divided into player and enemy phases where each side takes turns maneuvering their forces.
- Deploy the right troopers at the right time, and use contraptions found on the map effectively to achieve victory in battle!
- iPod Click Wheel allows players to play the game as easily as selecting music.