We had "cubby-holes" in the fininshed attic (I'm refinishing it right now). On the top "floor" of many early 20th century homes (mine was built in 1909) the walls are the insides of a 45 degree angled roof. Since one can't walk closer than 4 feet (or so) from the vertical exterior wall, there was a triangular storage space about 4' x 4' x 5.6568'...(Pythagoras to the rescue) built in with little doors for access. Talk about play time!