A few stops later, an older woman stepped onto what was a fairly crowded train. She was slight of build, and had a gauze patch over one eye. She looked quite solemn. Almost immediately, a young guy offered to give up his seat. She declined, and then broke out into this beaming smile - seemingly a reaction to his gesture. As the train filled in with other people, I could still see her standing there, quite beautiful indeed.
Footnote: I checked out the .com address, and it seems like a mix of actual grassroots activity (women leaving anonymous, positive messages in public spaces for other women) and viral marketing (you can buy an "official" t-shirt, which seems a bit odd for something that presents itself as DIY).