The Journal of Improbable Research’s report on postal experiments is a howl — JIR experimented by sending all manner of strange objects in stranger packages through the US mail and reported on whether the objects were delivered, and in what condition. They sent roses, human teeth in clear plastic boxes, a toy that screamed “Let me out of here!”, a hammer, a ski, a feather duster, a helium balloon, and many others. The USPS scored surprisingly high, though sometimes they added snippy notes, like this one, on the human tooth: “Please be advised that human remains may not be transported through the mail, but we assumed this to be of sentimental value, and made an exception in your case.”
Helium balloon. The balloon was attached to a weight. The address was written on the balloon with magic marker; no postage was affixed. Our operative argued strongly that he should be charged a negative postage and refunded the postal fees, because the transport airplane would actually be lighter as a result of our postal item. This line of reasoning merely received a laugh from the clerk. The balloon was refused; reasons given: transportation of helium, not wrapped.
(via Making Light)
See also Royal Mail delivers letter with no address, just a map
Update: Sharp-eyed Jesse spotted that I posted this story in 2003, albeit at another URL!
Update 2: Carl sez, “JIR (Journal of
Irreproducible Results) was killed off about 10 years ago. The link you
provide is to the new Annals of Improbable Research, which has the same cast
of characters but for legal reasons is “in no way associated [etc.]” with
JIR.”