It's the 40th anniversary of the Slurpee and for the sixth year running Winnipeg has won the coveted title of 'Slurpee Capital of the World' -- guzzling a record 400,000 every month.

Long before smoothies and Frappuccinos there was the Slurpee.

The slushy, colorful 7-Eleven brand might have turned 40 but it shows no signs of growing up. It's still popular today for the same reasons it caught on back then: fun, variety, "brain freeze" and colored tongues.

Slurpee was born in Kansas at a drive-in hamburger restaurant where owner Omar Knedlik served semi-frozen soft drinks from his freezer after his soda fountain machine broke down.

When they were a hit, Knedlik worked with a Dallas company to develop the "Icee" machine that replicated that consistency in slushy soft drinks served at 28 degrees.

When a 7-Eleven manager happened upon an Icee machine in a rival's store, he saw potential and got them into three stores in 1965. Within two years they were in almost every 7-Eleven and were renamed Slurpees for the noise they made through a straw.

Since 1965, more than 6 billion Slurpees have been sold. They're now sold in 17 countries. U.S. annual sales alone are $170 million.

Slurpees are now made by mixing syrup, carbon dioxide and water under pressure in a freezing chamber. In 1970, Slurpee marketing included Slurp magazine and a dance step and song called The Slurp.