Last week, my boys and I were camping along the St. Croix River, and we stopped in for lunch at "The Drive In" in Taylors Falls, MN. You can find it by looking for the 15' spinning Frostop mug:
That's the FROSTIEST mug of root beer I've ever had. Just look at that massive root beer ice berg inside that glass! It was sooo good after a hot hike in Interstate State Park.