there has to be a list of hobbies one can try that cost practically nothing:

Solving Rubik cubes (a high quality speedcube is about 20$)

Crocheting/stitching (needles and yarn after cheap)

Writing (free)

programming

… (please expand if you have any ideas)

IMO piracy and self hosting has great cost benefits.

Sure it costs money to buy a mini computer and a hard drive, but after, you can spend a long time building that library and it won’t cost you a dime.

And the computer and hard drive is more like an asset, you don’t really lose money when you buy it.

And it kind of pays you back, eventually you get a little tired of building your library but then you can use said library and integrate it into your lifestyle while you get a new obsession.