[notadoc]

What are you interested in? What are you working on? What do you want other people to know? Write about that.

> but almost every topic I think of has been written upon by someone

That same logic applies to almost everything, including most creations, products, items, professions, jobs, and certainly most business ideas too. What is truly unique and original? Not much. Some of the best ideas are simply new takes on existing things.