The rivalry between Coca-Cola and Pepsi is legendary. Although the feud really heated up with the Pepsi Challenge in 1975 —which prompted Coca-Cola's horrific New Coke debacle — the brands have been fighting each other for more than a century.
And not just about product development. Things occasionally get personal, which sometimes resonates in their marketing. Earlier this year, Pepsi went after Coke's famed mascots, the polar bears and Santa.
The feud has even moved into outer space and raged over social media.