Dissolve the sugar in the water in a gallon-sized, freezer-safe container. Stir in the grenadine, cherry juice, lemon juice, cherry brandy, gin, pineapple juice, and lemonade concentrate. Freeze for 24 hours, stirring at least twice during this time.
To serve, place 1/4 cup of the slush in a a glass, and top with lemon-lime soda. Garnish with a cherry to serve.