Is there a more civilized bar in Tribeca? (Well, maybe Brandy Library.) This is a cocktail bar in the Japanese style, with silver water pitchers, jazz on the stereo (or, some nights, played live), and a discernible devotion to the art. Half of the subterranean room is lounge seating; a quarter is bar; and the last quarter is booths (seats or tables can be reserved by calling). Wood paneling and glamorous lighting helps you forgive the lack of windows. The food is western as seen through a Japanese lens; the menu works for nibblers or those looking for a meal, or they can head upstairs to Ristorante Aglio, which is related to B Flat. Note: The happy hour deals (till 8 p.m.) are some of the best around.