Anyone ever watch "Doomsday Preppers" on the National Geographic Channel? One ham in Tennessee (he lives about an hour away from me) has his ham shack in a Faraday cage. He seemed a bit nutty, but nowhere near the other loons that have been featured on that program
I also remember reading somewhere that the damage that EMP can do on a nationwide basis is fairly limited. It would take dozens of nukes detonated in an air burst in numerous locations throughout the U.S. to wipe out every electronic device.
But knowing how to grow your own food and keeping an alternate power source at the ready is something I've been doing for years. Being prepped for hurricanes is a hard habit to break. Now we just worry about tornadoes.