There's an old, apocryphal story about a guy who was bitten by bedbugs in a train sleeper car. He wrote a letter to the railroad president. The railroad president wrote back, saying it was the first time he had ever heard of such a thing happening, he had ordered all the rail cars fumigated, and promised it would never happen again. The president also accidentally included a copy of the sender's original letter, on which was written, in the railroad president's hand, "Send this SOB the bedbug letter."
Earlier this week, Google launched the "bedbug letter" into the 21st century when it returned documents containing trade secrets to the original owner -- along with several incriminating Post-It notes revealing its plans for the newly acquired secrets.