If they only had one, it doesn't matter how much it cost them to make, it's worth much much more than $100 dollars to someone. If there were enough supply that it were possible for it to be only $100 then it would have to already be ubiquitous. I agree with jacques_chester that it's an economic distinction.
Change "able to produce" with "willing to sell for" and my point remains the same.
I agree that you're not going to get a "supercomputer" for less than about $100,000. But supercomputers are defined by what they can do. Their cost is secondary. Necessary in a world without magic, but secondary. I can spend $100,000 on a computer, but that alone does not make it a "supercomputer".
