A broker who lives in the Plaza estimates that only 10 percent of the owners live there full time—which means about 135 of 150 homes are empty more often than they are lived in. A former resident described sheer excitement when he spotted someone in the building: "When we saw somebody, it was a big thing. 'Oh wow, somebody's in my hallway!'"

The Time Warner Center seems to be the most transient of the buildings mentioned. A former resident said, "Our next-door neighbors were absolutely lovely, and we saw them maybe once a year." A Corcoran broker who sold in the building for eight years had buyers from all over the world, but not a single one from New York. He also never saw more than one person in the gym. "I've seen Kelly Ripa there. Two little kids were playing with Legos on the treadmill next to her, and there was nobody else." According to a Sotheby's broker, the north tower is just 30 percent permanently occupied, while the south tower hits 60 percent. Is it nicer there?

One57 isn't even finished yet, but we already know that the building will hold the quintessential trophy apartments. As the article says, "The higher the price, the higher the concentration is likely to be of owners who spend only a few months, a few weeks or even just a few days each year in their apartments." Apartments in One57 already fetched upwards of $90 million, and buyers have come from Britain, Canada, China and Nigeria, just to name a few.Photo via New York YIMBY

While not nearly as empty as many other places, 15 Central Park West holds possibly New York's most famous pied-a-terre: the $88 million penthouse that was purchased by the daughter of Russian billionaire Dmitry Rybolovlev. Rybolovlev's wife Elena sued him over the purchase because she said the condo wasn't bought as a place for their daughter to live but rather simply to keep the money out of Elena's hands.

The Sherry Netherland wasn't mentioned by the Times, but the article does point out that hotel/condo combination buildings have more pied-a-terres than regular condo buildings. And the Sherry-Netherland is a prime example. Judge Judy recently listed her pied-a-terre here for $9 million.