What Possible Uses A Domain Name Can Have For The End-User ?

I am listing some uses that I can imagine right now. Please help me to extend this list.

1) Replace the current domain name with a better one or the same name but with a more valuable extension ( like from .net to .com ).

2) Use the domain name to open a new company

3) Use the domain name to open a subsidiary company.

4) Use the domain name to promote a product with the same name.

5) Use the domain name to open a non-profit organization.

What Possible Uses A Domain Name Can Have For The End-User ?