Bruise the mint leaves in the bottom of a cocktail shaker. Add the lime juice, pineapple juice and shake the 2 together. In a medium bowl combine the lime and pineapple gelatins, and the sugar. Stir in the boiling water and whisk until the sugar dissolves. Stir in the rum and pour into the plastic shot glasses. Refrigerate until set, about 3 hours. Enjoy!