Writing, but even that is not all that expensive!
I pay like 40$ per year for my Grammar Checker, 40$ for my dopamine hits, I mean, 4thewords membership, 10$ for my Midjourney dopamine hits, I mean, supper important character designs, 100 or so $ for Canva Premium, but I will quit that next year since I don't think my victims, I mean, readers, need visual bait to consume my word vomit, I mean BL... nah, it is word vomit.
Became crack in recent days too.
20$ so that nobody will steal my AI brain vomit over at DA. Why anyone would want it, I don't know, but it has been stolen before. And I pay about 70$ per month for internet and phone, without which writing can't be possible.
Thinking about the electricity bill, food bill, and so on is too hard and leads to headaches. So I don't do it.
There are people out there who make money from writing, and I am here like:
Pay me in time and dopamine!