Mail Art
This is funny. Daniel Farrell and Richard Kegler sent stuff to each other from Buffalo to Albany from 1990 to 1996. There was a paint can with some dried paint in the bottom, and some radio parts mixed in. A sheet of glass sandwiched between a piece of copper screen and a piece of mylar. A mold of a human head. A piece of concrete went back and forth several times. A piece of polyurethane impregnated toast with a stamp and an address.
While they probably spent more time smoking pot and drinking beer trying to come up with things to do, it sure is pretty funny to fuck with the Post Office like that.