We have generally pleasant and calm associations with 941 Park Avenue, probably because Tom Brokaw used to live there. But the latest listing to come on the market in the building, PH15/16A, has a little quirk: an octagonal tower room! The price tag is a hefty $14.9 million. Then again, the tower room sits next to a pretty impressive terrace on the top floor of the triplex?the other floors include a library, four bedrooms, five full and five half-baths, and another nine-foot landscaped terrace wrapping around the second floor. Paging Rapunzel.