Fill cocktail shaker with crushed ice. Add 4 tablespoons sweet-and-sour mix, 2 tablespoons vodka, 2 tablespoons gin, 2 tablespoons orange liqueur, 2 tablespoons light rum, and 2 tablespoons tequila. Cover with lid, and shake until thoroughly chilled. Strain into 4 chilled small martini glasses. Pour 2 tablespoons sugar-free cola into each glass. Garnish with lemon slices, if desired.
Cocktail Tip Sidestep the extra calories by making cocktails with fresh fruit juices and calorie-free beverages rather than mixes, which are loaded with sugar.