I recently bought a new book: Edible, The Illustrated Guide To the World's Food Plants (see the side bar on the right). As I was browsing through, I noticed the name "Peanut Butter Fruit". Amazing... I had no idea there was such a thing! It's a tropical fruit that is native to South America. When it is just ripening into an orange colour, it gives the most crunchiest peanut butter flavour. It is typically used in preserves or blended into milkshakes or added to cakes.
How about that? You learn something every day.