I read something that resonated with me once that went something along the lines of this:

"Everyone should have at least 3 hobbies. One which brings you health, one which brings you joy and one which brings you monetary income".

I love swimming, which is great for my health.

I love reading, which brings me joy.

I have yet to find a hobby that doubles as a monetary source. 

What are some of your favorite hobbies? Do any of you have "side-hustles" or other hobbies which bring you supplemental income?