Killer app recommendation, Tricksy! For those iPhone / iPod Touch users that are interested... here's the official name and link to the app:
ZombieBooth: 3D Zombifier
I've seen some fun apps that can change your face (including "zombification" apps) but this one really stands out. For one, the gore effects are many and varied. The exposed teeth and rotting eye sockets are sick. There's an option to re-randomize the features, so you can keep playing necromancer until your cell phone itself goes dead.
But the real kicker is the 3D effect, animation, and sound. Your zombie photo moves, growls, furrows its brow, tracks your movement, and snaps at your soon-to-be-bloody finger tips if you touch too close to those chompers.
I've already had more than 99 cents worth of fun.
Here's my first infection via ZombieBooth:
Click for video version