(CANVAS STAFF REPORTS) - Get ready for brain freeze this weekend. On Sunday, July 11, 7-Elevens around the United States will hand out You must login or register to view this content. .

You can choose your favorite flavor, which might take a while because You must login or register to view this content. come in more than dozen varieties, from Coke and Mountain Dew to the more exotic Goji Berry Cherry.

The annual giveaway is to celebrate the Dallas-based chain's 83rd birthday. Whether you're budget-minded or just have a hankering for something cold and sweet, the Slurpee spectacular might be the pause that refreshes.

It is appropriate that this iconic icy treat will be served in 7.11 oz. cups.

Click You must login or register to view this content. find a store near you.

Slurpees have been around since 1967 and were named for the sound people make when drinking them. However, 7-Eleven did not invent these slushy sippers.

Like many how-did-we-ever-live-without-it products, the Slurpee's birth was an accident. In the late 1950s, Kansas Dairy Queen owner Omar Knedlik didn't have a soda fountain, so he stashed beverages in a freezer to keep them cold. This made the drinks slushy – which customers liked.

This led Knedlik to tinker with an old ice cream machine and eventually create the ICEE machine. He sold the machines to 7-Eleven in 1965 – and 2 years later, America was slurping. At least that's the story as told on Knedlik's You must login or register to view this content. fan page and You must login or register to view this content. .

Knedlik died in 1989. Perhaps someone will make a toast to him on Slurpee Sunday.

As for the company that turned the ICEE into the Slurpee, 7-Eleven has about 7,000 stores and franchises in the United States and Canada, according to the company's You must login or register to view this content. . Nearly 30,000 outlets are in business around the world.