This Saturday, 7-Eleven stores are doing something a little different. It's the first "Bring Your Own Cup Day." The fun of this is to see what kind of drinking vessels people will bring. A sandcastle pail? A trophy? The ideas are endless, but there are a few rules.

You can't bring a trash can as it's way too big. A boot or something else that could be deemed unsanitary is also out. They advice not to use something that would let the Slurpee leak through -- like a hat. Bring something clean that won't leak and is less than 10 inches deep.

Participating stores will have a guide you can check. If it fits the criteria, you'll be able to pour your Slurpee into the drinking container you brought.

This is only at participating stores, though, so make sure your store is doing this promotion before you start dumping Slurpees into your favorite cup.

USAToday has more info on this special occasion.