This undated photo supplied by Hilton Worldwide shows a 13-story work, "Loopy Doopy," by Sol Lewitt in the lobby of the Conrad New York hotel in Manhattan. Each guest room has a tile on display representing part of the work and the tiles are also sold in the hotel boutique, part of a trend of hotels differentiating themselves with unique works of art and then offering copies of the art for guests to purchase. (AP Photo/Conrad New York)
