I mailed a prototype audio mixer to a client of mine in Tucson, AZ, via Priority Mail. It was built on proto-blob-board, with a bunch of pots connected to it.
The package arrived at the clients house today. On the outside was attached one of those USPS letters that says "We're sorry your package was damaged in transit. We make every effort to blah blah blah."
He has video documentation of what happened right after he opened the package - it was just an empty box. The Priority Mail flat rate box had been ripped open from the side, and the circuit and packing removed. They just delivered him an empty box along with the letter saying the package had been damaged in transit.
I'm fairly certain that the reason for this is that somewhere along the line the package went through a scanner or something, they decided they didn't like the look of what was being sent, and they pulled it.
Next steps?