I just finished my second snowball from Sweet Caroline on Burnet Road. The small is big enough for me. The ice is shaved and so soft and fluffy. They have tons of flavors and they are very generous with the syrup. I've had raspberry and pomegranate. I've also ordered mine with a scoop of vanilla blue bell in the center.
I've seen a few snowball, snow cone places on Burnet but haven't tried the others. Lets know if there are other places I should try while its 1,000 degrees outside.