I understand the fact that you are joking. But I am curious to know if something like this really can happen in the future. These jokes are old now. But what if the tech guys really make something that would be able to do it? If something like that exist, it should be able to bruteforce the bank of America website and hack billions of dollars, right? So what these banks are going to do?

Ah, it seems the world is going to run without any money or with just fiat and off-line transaction again due to these quantum computer. 
They simply won't be able to break the encryption. The government wouldn't allow them to operate if they could do something like this.