Here's an interesting piece I picked up maybe 20 years ago and haven't seen again since:
it is a tale of the tape boxing promo for venues to hand to patrons to publicize a showing of the fight.
And as long as we are talking beer:
Mid 1950s promo card for Cuban beer, this one signed by Valdes.
Joe Louis shilling for Canadian Ace beer. The company was long a front for organized crime and was trying to go legit when this was issued in the 1950s.