1. Line eight 2-1/2-inch muffin cups with paper bake cups; set aside. In a medium mixing bowl stir together flour, baking powder, ginger, cinnamon, soda, and salt; set aside.
2. In a small mixing bowl stir together the egg white, molasses, water, and oil. Stir molasses mixture into flour mixture just until blended. Spoon mixture into prepared muffin cups.
3. Bake in a 350 degree F oven for 15 to 20 minutes or until cupcakes spring back when pressed lightly in center. If desired, sprinkle with powdered sugar. Serve warm or cool. Makes 8 cupcakes (8 servings).