If you're a secret double agent for the CIA, or if you're a government conspiracist, or if you're a former Wall Street CEO that needs to hide your bank records, have we got the solution for you! This hack we found on Instructables tells you how to wire up your USB flash drive and access your files from behind a wall-mounted phone jack. Just make sure you delete your cookies once you're done building, or else they'll find you and your hidden files.
By taking a standard USB cable, stripping the four wires, and then connecting those wires to either end of a telephone line jack and port, you’ve got a way to inconspicuously access as much info as you need hidden.
Check out the step by step from Instructables user stonehenge360 here.