I bought a new car in May (the first NEW car for me) and while I am not a clean-freak, I can't stand streaked and spotty windows. I've tried vinegar, ammonia, newspaper, cornstarch, etc., but was never happy. I remembered a microfiber cloth I bought about 10 years ago and never really used for much other than dusting and thought I'd try it, and WOW! I can't believe how beautifully it cleans the windows - and everything else. Soap scum on the shower doors, gooey residue from tape or stickers on plastic and glass. Every time I use it I try it on something different. I can't believe I let it just sit in the linen closet for 10 years.