World War Z- Max Brooks.
An oral history of the zombie war.
This is one of the most amazing "what if" books I've ever read.
What would really happen if a zombie plague actually spread worldwide?
Told as a series of interviews with survivors, this book rigorously examines all the effects that a fast moving plague might have on modern society.
The is no sensationalism and little gore...it's not a Stephen King style novel, rather an academic treatise that reveals it's insights through personal narration.
All aspects of the turmoil- political, religious, military and cultural- are brought to light as various survivors talk about their experiences.
I found it frighteningly plausible and compulsively readable.