there are several buildings like this in Manhattan. https://www.cromwell-intl.com/travel/usa/new-york-internet/p...

yeah, it looks less basic than a concrete block, but it is just a big box. this small skyscraper could offer a nice view, but it has no windows.

they used to be filled with telephone switching equipment for all the phone lines, but electronic switching has shrunk those space needs a lot. I think they've turned them into hosting providers for financial companies but I'm not positive.