Of the various tools made for extracting the flesh of a pineapple from its shell quickly, the all-plastic, easy-to-clean, Dutch-made Vacu Vin corer is the first I've encountered that is very easy to use and empties the shell without piercing it.
You first cut off the pineapple top to expose the fruit, then twist the tool down into the fruit to cut it into one long, uniformly thick spiral. The Vacu Vin base supports the spiral as you lift it from the shell. Just pop the handle free and slide the fruit from the corer's stem.
Drain the juice from the shell (if you want to use the shell, cut the tough core out with a grapefruit knife). Slice the fruit any way you like and fill the shell with a drink, dessert, or salad. You'll find this pineapple corer in many cookware stores; it comes with one or three coring units, each geared to specific fruit sizes.
A cool milkshake makes a perfect filling for a pineapple shell. For harvest-sweet flavor, try this one with the new Del Monte Hawaii Gold pineapple. Sure, the shell container is just for fun ― a few tall glasses can do the same job, but they fall short when it comes to conviviality.