In 1960 Peru issued an airmail stamp with a world map on the back of a Peruvian cormorant flying over the ocean. It was issued to mark the International Pacific Fair in Lima, Peru.

     The "projection" is vaguely like the Lee conformal tetrahedric projection, or Adams conformal rhombic projection, but it appears to me to be most like Barlow's tetrahedral projection. The angles have to be modified to put the projection on the cormorant's back, so the map is not really on any projection. It is, nevertheless, an interesting concept.