From The Atlantic Espionage or Journalism? After the Snowden NSA Leaks is it paranoia if they really are after you?
Soltani and I used laptops from which we’d removed the Wi-Fi and Bluetooth hardware, and disconnected the batteries. If a stranger appeared at the door, we merely had to tug on the quick-release power cables to switch off and re-encrypt the machines instantly. We stored the laptops in the vault and kept encryption keys on hardware, itself encrypted, that we took away with us each time we left the room, even for bathroom breaks. We sealed the USB ports. I disconnected and locked up the internet-router switch in my New York office every night. I dabbed epoxy and glitter on the screws along the bottom of all my machines, to help detect tampering in my absence. (The glitter dries in unique, random patterns.