Someone was grinding metal on a car somewhat close to mine, and now I have rust specks all over my windshield. Anyone have any experience removing the rust stains and pitting caused by the sparks?

You could try CarPro Iron X Iron remover. I detailed a lot of new cars when I was younger and many of them that come off train, will have tiny rust specks in the paint. This stuff dissolves them safely. Should work on the windshield too. Good Luck!

Thanks for the tip, I'll look into it.