I just saw the oddest thing I've ever seen on a subway platform

A woman had a cigarette lighter in one hand, and was trying to light her other hand on fire. She kept lighting a flame and putting her index finger next to it, like she was, I don't know, trying to burn off a wart or something, and then it would get hot and she would shut off the lighter and she would shake her finger, in some obvious pain, until it cooled off. And then she would do it again.

This was very strange. And I walked down the platform a bit to be sure I wouldn't end up in the same car as her, since who knows what else she wanted to light on fire.