Cut bananas in half lengthwise, then cut each piece in half crosswise. (You should have 12 pieces.) Stir together margarine or butter and 1 teaspoon of the lime or orange juice. Brush mixture on all sides of banana pieces.
Place bananas directly on the grill rack over medium-hot coals. Grill, uncovered, for 2 minutes; turn over and grill for 2 minutes more or until heated through.
Meanwhile, in a heavy, medium skillet or saucepan combine the caramel topping and the remaining 1 teaspoon lime or orange juice. Heat on the grill rack alongside bananas directly over the coals, or on a stovetop, until bubbly, stirring frequently. Stir in cinnamon. Add bananas and stir gently to coat.
To serve, scoop ice cream into 4 dessert dishes. Spoon sauce and bananas atop ice cream. Sprinkle with the coconut and/or almonds, if desired. Makes 4 servings.