Some of the hobbies I like to do is woodworking, fishing, camping, working on cars, working with computers and blogging.
I started a blog as a hobby just writing about things that I knew and know a lot about and thought would be helpful to other people.
Then 10 years later of blogging I started making enough money to quit my day job.
Now I can do anything I want too without having to go to work.
I still blog but only when I feel like it and all those blog posts years ago still make me money.
I also make some money off of Youtube which is another hobby I started and then made money on that a few years later.