1) Cut out a large piece from top of each cantaloupe and remove seeds.
2) In small bowls, stand the cantaloupes securely and sprinkle the cavities with powdered sugar.
3) Scoop out balls from the honeydew melon, fill into the cantaloupes, then pour in the wine.
4) Refrigerate to chill for several hours.
5) In a bowl, drain the melon balls and wine from the cantaloupe, then slice the cantaloupe into serving pieces.
6) Add a sherbet scoop, cluster of grapes, then pour over the wine and serve the chilled Cold Melon Surprise.