[purpleRac3r]

Yes, there are. First, try an automotive specific glass cleaner instead of regular Windex. They have special ingredients for cutting grime and dirt not normally found inside a house. I also use only high quality microfiber cloths. If this doesn't work, Mothers, and probably others, have a water spot remover for glass. Its actually a very, very fine polish. Works quite well based on the one use I had for it. But it does require a little elbow grease. Everything should be available at your local auto parts store.