The Tube is the great equalizer of London. Stand on a platform long enough, and you'll see ballet goers alongside opera lovers, brushing past nurses, students, proper city lawyers, grandmothers speaking languages I can't place, aunties heading home from the market, kids on their way to school. Rich, poor, every color, every accent, every continent — all of it. London in a single carriage. All for the cost of a Tube ride.