The classic and cliche "when you stroll up to the train and it immediately arrives, so you can hop on without missing a beat"
Sharing a knowing look with a stranger in public as chaos ensues in the vicinity (see: "It's Showtime!")
That limitless sensation when hopping on a local, almost empty bus on a sunny Friday afternoon with the intent to pass some time with a pint and the New Yorker at a Brooklyn bar (i.e., Judy's in Sunset Park). I am done with work--or, at least, work can't find me--and I am embodying the Joni Mitchell song "Free Man in Paris."

Sitting in the window seat of the N or D train in the late afternoon, after a day spent traipsing around Manhattan, with my head against the window. The train slowly lulls me into a drowsy reverie. The other passengers are well-behaved, quiet, often older folks, and it's a relaxing atmosphere for all.
Finishing an epic long run during marathon training (16+ miles) in the middle of Manhattan, the greatest city in the world. I have only my phone and my keys in my pockets, and I am able to choose from a slew of snack options before taking the subway home to Bay Ridge.
Sunset walks along Shore Road across the seasons. There's something to appreciate about each season's particular qualities. In winter, there's the exquisite juxtaposition between the warmth of a cuppa and the frigid wind roaring across the Narrows. In summer, there's the sensation that--with the children screaming in delight, the fireflies out, the elderly couples strolling hand in hand--it could be 1989. There are no screens around. There's no need for the omnipresent cloud. A pit stop at Carvel or the ice cream truck on the way home is a necessity.