Eyes lock for the briefest instant in recognition, then divert, as bodies balance coffee, cokes, trenchcoats, umbrellas and bags, filing in chaotic, inverted-v order with the kind of muted urgency of people who know the doors will shut all too soon. Now is too soon to speak.

Ding. Slam-wham. The doors try to set their limits but are quickly and violently denied by one last body breaking the infrared sensors.

Finally they close.

"Seventeen please", someone calls out from the back. The poor soul, we know he'll have the agonising wait whilst every single other floor is stopped at.

People jostle, look around at the nothing to look at. Eyes meet again,

"Hey"
"Hey how are ya?"
"Good, good. You?"
Smiles exchange.
Silence.

Ding.
Smiles. Negotiates self, Starbucks and bag out of the doors.
"Seeya"

Finally it's only Floor Seventeen and you left. This facilitates a deeper conversation than just greetings.
"Good weekend?"
"Yeah, great, only worked half of it"
"Excellent! You very busy at the moment?"
Half smile and "Yeah, pretty much"
Sympathetic half-smile return "Yeah, same here"

This has been the hard bit, choosing a topic and saying just enough on it to elucidate a conversation that is just perfect for the time it takes to go between destination floors. Therein lies the art.

Ding.
"Take care"
"See you".