If when you read THE.CAT you see something different in this domain from other names of domains maybe what you are seeing is that THE.CAT is a DOMAIN HACK.
Let me put a list of other domain hacks:
To know more about domain hack:
In the above link there is an explanation of domain hacking and there is also a list of domain hacks. I have also found a domain hack list at:
They mention a .cat domain hack: KITTY.CAT
To search or create domain hacks:
If you want to buy domain hacks there is a web only for that!: