I make this with watermelon, and add minced chocolate mint leaves. (There is a mint plant called "chocolate mint" that I grow on my balcony.)
From EatingWell: July/August 2009
This granita uses sweet ripe melon for flavor, apple juice instead of sugar and a touch of lime juice to perk up the flavors. Berries look beautiful on top; or if you can find fresh figs, add them. For a vibrant look, make with an orange-fleshed melon, such as cantaloupe, Charentais or orange honeydew.