8 cups (1/2-inch) watermelon cubes
1 1/2 cups ginger ale
1/3 cup water
1 (6-oz.) can frozen limeade concentrate
Place watermelon cubes in a single layer in an extra-large zip-top plastic freezer bag, and freeze 8 hours. Let stand at room temperature 15 minutes.
Process half each of watermelon, ginger ale, water, and limeade concentrate in a blender until smooth; pour mixture into a pitcher. Repeat procedure with remaining half of ingredients; stir into pitcher, and serve immediately.
Honeydew Cooler: Substitute 8 cups (1/2-inch) honeydew melon cubes for watermelon cubes and 1 (6-oz.) can frozen lemonade concentrate for limeade concentrate; proceed as directed.