Peel, core and cut each pineapple into six spears. In a small saucepan, melt 6 tablespoons butter with sugar and nutmeg. Brush over pineapple. Grill, covered, over medium heat or broil 4 in. from the heat for 7-10 minutes or until lightly browned, turning occasionally.
For sauce, in a small saucepan, melt remaining butter. Stir in brown sugar and cream. Bring to a boil, stirring constantly. Remove from the heat; stir in vanilla and salt. Serve sauce with ice cream and grilled pineapple.