Dark Shards.
Needle towers, supertalls, skinnies.  What's happening on 57th Street right now has no precedent in the history of building:  the four tallest residential towers in the western hemisphere will all soon stand on a single street a couple blocks below Central Park in Midtown Manhattan.  

Urban defect?   Likely, if, as anticipated, all of the units end up in the hands of sheiks and oligarchs who live elsewhere and only spend time in these otherwise dark shards for a couple weeks a year.