I pushed a woman while getting off the train today. I know, I surprised myself when I did it.
Etiquette dictates that as the hordes leave the crowded train, anyone on the platform stands to either side of the door. But the young woman in question never got the etiquette memo. She stood her ground, smack dab in the middle of the way ... wearing headphones. That universal symbol of refusal to participate in society; the magical talisman that protects you from having to give a fuck.
I watched four people in a row have to stop and side step around her, while she stared straight ahead in her headphone smugness. So, when my turn came, I stepped to the side and checked her with my shoulder as I passed. I didn't psych myself up for it, and I didn't apologize afterwards. Probably not the correct multiple choice answer, but it felt really empowering.
It helped that she was shorter than me.