Original Use: Making cakes rise.
Aha! Use: Wash items, then place on aluminum foil in the bottom of a pot. Add a baking-soda solution (1/4 cup soda, a few teaspoons salt, 1 quart boiling water) to cover for a few seconds.
Reward: A chemical reaction that gets the black off the gravy boat.

Note: make sure to use a large pot and add the baking soda and salt to the water before bringing it to a boil.