Photonica
(Photonica)
35
When I was in the service, the only approved way to ship classified information was USPS first class. I could legally take a SECRET research report, wrap it in brown paper, address it, and mail it to the recipient. It was recommended that we get Signature Confirmation, but once it was handed across the post office counter we had no idea where it was until it arrived a couple of days later. We were legally forbidden from sending the same information FedEx or Airborne, where we could track every time it changed hands and it would arrive the next day. Got to protect the Post Office monopoly!