Mix together the rum, honey and lime. Rub the whole pineapple in this mix and leave to marinate for 2 hours.
Grill the pineapple for 3-4 minutes on each side. If there's any mixture left, brush over the top while grilling. Slice vertically and core the hard centre, then chop into pieces. Serve with a scoop of ice cream and top with the coconut.