For a couple of years beginning in 1989, a trio of Italians made several hundred postage stamps and used them to send letters through their country's notoriously slow and inept postal service. The hand-drawn stamps tended towards the satirical and the comic: one that featured a picture of an Italian porn star called for protection of endangered species.
JGS Boggs is an artist known for making meticulously rendered drawings of currency. Instead of selling these one-sided "Boggs bucks" for money, Boggs attempts to use the art as money, in exchange for goods and services. He does not consider the artwork complete until such a transaction has taken place with one of his bills (or "notes", as he prefers to call them).
F.I.R.E., or First Issue Reserved Edition, is a "unique collection of U.S. postage stamps" created by a self-described "terrorist/artist living and working in New York's East Village." The F.I.R.E. web site displays its stamps under three categories: life, people, and commemoratives. Most enshrine ideas, people, or objects of American culture that would never appear on official U.S. postage stamps: guns, the homeless, friendly fire, Jack Kevorkian, Waco. A stamp commemorating the atomic bomb is captioned "shame on US".