Composer-lyricist hopefuls and established talents show their stuff until 4 am, seven nights a week, at this convivial Theater District cabaret. Extroverts will be tempted by the piano bar's open-mike policy as well as by the other showroom's singers, comedians, or drag acts. Those needing a break from the above can find it in the quieter exposed-brick lounge. Our only questions: "Who's Mama?" and "What exactly is it that we're not supposed to tell her?"