Apparently someone had too much time on their hands...
http://www.snopes.com/business/graphics/pepsisex.jpg
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In the summer of 1990 Pepsi got in trouble for one of their Cool Cans promotional cans.
If you took 2 cans, twisted the top can to the right, the bottom one to the left, and kind of squinted, you could make out a word that looked like 'S-E-X' with the loop of the first 'P' forming half an 'S', the 'E' missing its bottom half, and the second 'P' crossed by a neon bar that makes it look like an 'X.'
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