Nazi Zombies Portable Dynamic Theme for PS3. This is for the PlayStation 3, not the PlayStation Portable.
Place nzp.p3t into your usb drive, like so: [USB]/PS3/THEME/nzp.p3t
Then connect your usb device to your ps3, and go the the theme section on the xmb. Go into it and press X on 'Theme' and then choose install. Select your usb device and then choose the theme to copy.