Operation Cornflakes was a World War II Office of Strategic Services PSYOP mission in 1944 and 1945 which involved tricking the German postal service into inadvertantly delivering enemy propaganda to German citizens through the mail.

The operation involved special planes that were instructed to airdrop bags of falsely, but properly, addressed mail in the vicinity of air struck mail cars of trains. When recovering the mail, the postal service would hopefully confuse the false mail for the real thing and deliver it to the various addresses.

The content of the mail often included copies of Das Neue Deutschland , the Allies' German language propaganda news sheet . In addition, the postage stamps used were subtly designed to resemble the standard stamp with Adolf Hitler's face, but a close examination would reveal that his face is made to look like an exposed skull or similarly unflattering imagery.