Today is the day that the obscure, yet very powerful, Board of Standards and Appeals hears the appeal of its decision late last year okaying the Finger Building pending the outcome of legal cases. The building at 144 North 8th Street has been stuck at 10 stories for more than a year as the legal fight plays out. In the meantime, the rusting, partly finished hulk has loomed over the Williamsburg landscape, quite visible because it is the tallest building in that part of the neighborhood. Resident groups argue that the permit for the building isn’t valid because architect Robert Scarano and developer Mendel Brach counted neighboring roofs as “open space.” The building may also have changed ownership. All should be more clear in a few hours.