On our way to Alaska earlier this year we got a windshield chip about the size of a nickel. When we stopped for the night I called a local glass company to come out to fix it. While they did a job adequate to stop it from spreading it's still highly visible.
Later in the trip we got a several more dings about the same size. Rather than call another glass company I stopped at an auto parts store and bought a windshield repair kit made by Permatex. I followed the instructions and fixed all of them with a single $12.00 kit. It did an excellent job. The only ding you can still see is the one fixed by the glass company.
I now carry one of the kits in my tool box.