Looking through ebay tonight I found a seller with a 1981 issue of a stamp issued in the island nation of Comoros, commemorating approach and landing tests of the Space Shuttle Enterprise. There have been a *lot* of spaceflight related stamps issued by dinky little nations; my assumption has always been that this is a reasonable and understandable way for these small countries to make a little scratch from foreign stamp collectors, rather than as a way to mail letter.
Anyway, this particular stamp comes still attached to a souvenir sheet. Additional artwork on the sheet includes the starship Enterprise (linking it to the Shuttle), a Boeing X-20 Dyna Soar, which I’m a little surprised they were even aware of, and a portrait of Austrian rocket engineer/scientist Eugen Sanger, who died in the 1960’s. An unusual bunch to see together.