Most of these are in-jokes, as I suspect most official post
office issues are also. So if you don't get it, don't fret -- in a hundred
years others will scratch their head at things like the USPO "Elvis" stamp.
Please
select
from
the
index
at
left
Note: viewing depends on allowing background images -- set this
with
your browser (although it is likely the default). If so set, the
background here will be gray.