Zombie Apocalypse: The Song :-)

A songwriter friend of mine and I occasionally get into these little...arguments, and they almost always culminate in some sort of challenge. Recently, he accused me of writing hundreds of songs about the same two or three topics. We'd been drinking many a Sam Adams, so I said, "I can write a song about anything you can think up..." He said, "Okay, write a song called Zombie Apocalypse." So I did... :-)