I don't know that a lime tree should be referred to as a product, since it is a living thing created by Nature herself, but I did want to call attention to the benefit of growing your own Kaffir lime leaves if you are a devotee of making your own Thai food.
I purchased a small tree at a local nursery, and I have been growing it in the same ceramic pot that I transplanted it into four years ago. Just like growing your own rosemary, thyme, oregano and other culinary herbs, it is convenient and a money saver to have the tree available year round. I really dislike trying to find the leaves when I need them, because they are not always available at a regular grocery store, and they are expensive. Place the tree in a sunny spot, water, fertilize occasionally and protect from frost, and you will be rewarded with a carefree little tree that offers up beautifully aromatic leaves any time you need them.