How Small Is the World?

Today I got on the subway to go home and I was standing next to the same woman I stood next to this morning. This was highly strange and unusual given that it was rush hour both times and there were literally hundreds of people on the platform that we stood on, not to mention in the car we got into. But what was truly strange was that tonight I not only got on the train at a different station than I had gotten off of this morning- I was riding a totally different line. We both got on and got off at the same stops this morning and then got on and got off completely different stops at the same time tonight. And we weren't just on the same car, we were standing directly next to each other both times. I thought to myself, "If ever there is a time to instigate conversation with a stranger here in NYC, this is it." But, as it turns out, there isn't ever such a time, because I didn't.

If I had, what should I have asked her?