Crystal Light Slurpees!
Ok..........maybe I just caught them on a bad day, but when I tried one it was so incredibly strong flavored and disgusting, I had to spit out the sip I had taken and throw it away. Maybe it was just a bad batch since you all seem to like it so much. For a while, my local 7-11 had diet pepsi slurpees that were sweetened with Splenda, those were really great, but they didn't last long at that store. Oh well, I guess I'll just stick to my occasional Starbuck's splurge.
hey beth, here's a thought. ok so it's NOT a slurpie or anything BUT, it's a close second AND it's good for you too 
i take a 24 oz. bottle of water each day and i drink about 3-4 ounces out of the top of it to make room. then i put in one strawberry-kiwi flavored special k2o protein mix packet, one strawberry flavored crystal light packet and then two pink lemonade flavored all bran mix packets. then i freeze it for a couple of hours (not solid though), take it out, shake it up REALLY good and viola! a sweet/tart slushy that gets me "going" AND gets my water in for the day. when i mix it up this way then it equals 30 grams of carbs, 25 grams of fiber, 5 grams of protein and only 70 calories in a 24 ounce drink. (<--but you can tweak it however you need to of course, lols.)

i take a 24 oz. bottle of water each day and i drink about 3-4 ounces out of the top of it to make room. then i put in one strawberry-kiwi flavored special k2o protein mix packet, one strawberry flavored crystal light packet and then two pink lemonade flavored all bran mix packets. then i freeze it for a couple of hours (not solid though), take it out, shake it up REALLY good and viola! a sweet/tart slushy that gets me "going" AND gets my water in for the day. when i mix it up this way then it equals 30 grams of carbs, 25 grams of fiber, 5 grams of protein and only 70 calories in a 24 ounce drink. (<--but you can tweak it however you need to of course, lols.)