White Vinegar is great to use, if you want to get rid of hard water stains and make your glasses sparkle. Take a clean glass, and let it soak in warm water with white vinegar (about 1 to 1 ratio) for at least 10 minutes. If the glass has heavy hard water stains, I suggest you let it soak over night. Then dry it with a clean tea towel. I did this to our “Mad Man” glasses, that we found on our first antiquing trip, they looked all cloudy and the silver band had hard water spots. After washing them, I let them soak for about 15 minutes, and dried them. The cloudiness was gone, and the silver bands where nice and shiny!
I use white vinegar for EVERYTHING. I add a 1/2 cup of white vinegar to the dishwasher every time I use it, and I never have any hard water stains on any of my dishes or silverware.