Ack! It was raining the other day, so, obviously, I had to use my wiper. Well, yesterday, getting into my car, I noticed that the driver side windshield has a fine scratch/mark on the area where the tip of the wiper blade passes through. Looks like a little rock got between the rubber piece and the glass. I'm not sure if it is an etched mark or just sedimentary deposits. I've tried rubbing it off but with little results. I'm still not sure if it is a permenant scratch or not. How can I get rid of it, as it is somewhat visible and distracting.

Oh, also, is there anyway to get rid of windshield nicks caused by bouncing rocks on the freeway? Thanks.