More on Corner Card Covers

I started a new post as I feel I incorrectly referred to a "return addressed
envelope" as a corner card. I have covers that I receive in my daily
business mail that have colorful and sometimes graphic designs in the upper
left corner of the envelope as the return address. I wouldn't say that they
are really advertising as I would describe a corner card. So, does anyone
collect different style "return address envelopes"? Examples might be
envelopes with the return address of a hotel, an amusement part, an air
conditioning business or sherriff's department.

Jim Pettway