Is it just the electronics devices like notebooks, PC's that are rendered useless or as well the actual storage mediums like flash memory & optical discs even when there stored away? Would data on usb external HDD, flash memory, & dvd optical storage be readable after the attack? What home methods can keep these storage devices safe? Do the devices (usb flash & say notebook) have to be connected to power in order to be affected by the emp? Would wrapping devices in alot of tin foil & storing them in a safe be enough? I'm not getting ready for ww3, but I'm pretty curious.