When dinosaurs roamed the earth and Groucho Marx stalked Beverly Hills (that would be 1945), the mustachioed jokester pioneered an early form of social networking.
As the Marx Brothers' A Night in Casablanca, a spoof of the popular Humphrey Bogart picture, was in production, attorneys from Warner Brothers (the studio that produced the Bogart "Casablanca,") requested information about the one where Groucho plays a trench-coated guy name "Humphrey Bogus."
Smelling a publicity bonanza, Groucho wrote an open letter to Warners as though the studio were suing him and his siblings for appropriating the name of the Moroccan city. And since the best defense is a good offense, Groucho reminded studio attorneys that since the Marx Brothers predated the Warner Brothers, there might be litigation.
Groucho's open letter to the studio had the effect of generating free publicity for the film and getting the public on the side of the madcap brothers. It might be said that his letter is funnier than the movie itself.