Marry Me a Little (Keen Company, Clurman, 410 W. 42, closes Oct. 27). A 70-minute jukebox musical–one set, two actors and a pianist–about two young apartment dwellers who live on adjacent floors of the same building and dream of finding romantic partners. The score consists of little-known songs by Stephen Sondheim, most of which were cut from his shows prior to their New York openings. Short, smart, and sweet, and Lauren Molina, who plays “Her,” is extraordinarily good (TT).