Slurpee exists because a Kansas soda jockey had no working fountain.
Omar Knedlik, running a Dairy Queen in 1958, froze bottled sodas and sold the sodas half-frozen. Customers loved the slush, so he spent five years building a machine to make it, the first prototypes running on a salvaged car air-conditioner. He licensed it to 7-Eleven and collected royalties until the patent expired. 7-Eleven now sells about 14 million Slurpees a month.
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