It’s a doable common hobby for middle class Americans. I grew up in a rural area with a dirt airstrip and everyone owned planes- even people that could barely afford a reliable used car. You can sometimes find something like an old Cessna for about $20k, and if you’re willing to do “experimental” planes that you fix yourself, sometimes just a few $k. Like anything, if you’re an insider in the community you can get good deals, sometimes even free from friends that age out, etc.

Many universities in rural areas have student clubs that offer lessons and rent club owned planes for cheap.

A lot of people fly. It's pretty common to be a fractional owner in a relatively inexpensive airplane and use it one day a week or some such.

It's sad that more countries outside of North America haven't actively developed their general aviation industries. It's never going to be cheap (or safe) but there's no good reason to impose the high taxes and regulatory constraints that keep it should be out of reach from regular upper-middle class people in many countries.

Fiberglass sailboats last forever and the hobby is dying as people age out of it. I’m in the sailing community and get offered nice free boats in usable condition every year, but already have 2 so refuse any more. This year alone I’ve turned down both a 40ft and a 23ft free boats from 80-90 year old friends that aged out. Parts are expensive, but if you can do repairs yourself, you can absolutely own a pretty nice sailboat for about what it costs for a new apple laptop. I paid $1800 at auction for my most recent sailboat and it is only 7 years old, and needed nothing. Did an overnight trip on it recently.

I want to find a way to revive the hobby by showing younger people short on money that they can get into sailing for less than they already spend on much less rewarding stuff like app subscriptions and smartphones.

Knitting / crocheting / quilting / embroidering? Drawing / painting / calligraphy? Singing in a choir? Creative writing / journaling / blogging? Solving crossword puzzles? Bird watching? Day hikes? Reading? Visiting museums? Learning about history / philosophy / art / whatever? Learning a language? Taking dance classes? Playing chess or petanque or any other game that doesn’t require expensive gear? Or most sports?

A lot of things are cheap to taste — a second hand bike and some $200 running shoes and you’re training for a triathlon. Or a makerspace membership and you’re now sewing or doing 3d printing.

It’s once you get “serious” and need to have your own equipment that all these things get real. Or in the case of things like social dance, you want to take time off with and travel further and further away to attend pricey exchanges and camps.

Besides programming, my hobbies are writing stories, writing and recording songs, drawing, and painting. None of them needs to cost anywhere near $3000. Any of them can cost as much as you want.

Take the music hobby as an example. I have several expensive guitars now, but in the first 20 years of that hobby I probably spent under $1000 on guitars and related gear the entire time.

Running. You only need good shoes, really. Words from coworker running marathons.

For me the only one would be sketching/painting. But I agree with the point in general, most hobbies cost a lot.

cross training ?

I can not think of many hobbies which are less expensive if you are serious about them. Some hobbies around me, where $3000 wouldn't get you far: Motorcycles, cars, cycling, collecting anything, woodworking, machining, music making, traveling, horses,...

There’s some nuance to it.

Judging by the authors preference for Linux, I’m guessing this hobby has some professional applications as well.

$3k is the price of a very nice guitar, but I am not about to casually shell out that money every few years.

However, I earn my wage using a computer, so it’s a lot easier to justify staying relatively current on specs.