Opposite Rikers, on the other side of the river, there is an enormous white and blue ship that appears to be made of big lego blocks. According to Wikipedia, the Vernon C. Bain Center is an 800-bed jail barge used to hold inmates inmates in a medium- to maximum-security setting. The Boat (the staffs and inmates nickname for the barge) was brought to New York in 1992 to reduce overcrowding in the islands land-bound buildings for a lower price.
There be noon-time basketball there, too.