When Southwest began using the motto "Just Plane Smart," Stevens Aviation, which had been using "Plane Smart," advised of infringing its trademark. Instead of a lawsuit, the CEOs staged an arm wrestling match. The loser paid to a charity of his choice and the winner claimed the motto.
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When telephones first came into commercial use you had to whistle loudly into the receiver to get the other person's attention, as telephone bells hadn't been invented yet.Source