Years ago, I had heard that it would cost over 100K to buy a Toyota Corolla if one tried to purchase it piece by piece. It seems as if manufacturers really sock it to 'ya when buying parts.
Now, I've another example to add to this phenomena: Not wanting to be without a spare, camcorder battery when on vacation, I thought it'd be necessary to buy an extra one. It is lithium, but very small. You can see the actual size by comparing it to a quarter in my photo. The Sony NP-FP50 battery cost $89 before taxes!