Stubborn stains or wine residue that linger on the bottom of narrow-necked vases or decanters can often be tricky to remove using standard methods. Once again, Alka-Seltzer comes to the rescue: Fill the container halfway with water, and drop in two tablets. Let stand until the fizzing stops, and then rinse the vessel thoroughly with plain water. (The container may need a second application if it's extremely dirty.) You can also use this method to clean a dirty glass thermos.