These marshmallows are not only packed full of caffeine, but they are also a licensed Ghostbusters collectible. It’s not often that you can eat a collectible. They come in a rubbery marshmallow-like box that can be reused after you’ve eaten the gourmet marshmallows. Each one of the boxes comes packed full with 16 square marshmallows. You can purchase one of them for $19.99 through Think Geek.