We had some friends over the other night for a bbq and they brought the yummiest glazed pineapple I've ever had...it was delicious and so easy.
1/2 cube butter melted
1/2 cup brown sugar
1/2 tsp cinnamon
(this is mostly a suggestion you can change it to your liking)
Mix well and soak sliced pineapple for a few hours, grill until nice and caramely.