Ask Lemmy

Scrap metal - if you have a truck you can cruise neighborhoods on trash days and get metal scrap. beware the long time scrappers though, don't piss them off by treading on their turf.
Plasma - depending on where you sell your plasma, you could make around $200 a week. You could also make a LOT less and end up with nasty track marks on your arm.
Day labor - Theres probably a day labor place near you that you can go to and get a days work. They will send you somewhere different each time. Its usually tough physical work but the pay can be decent. Downside is you usually need to be there around 4am.
Upselling - if you get lucky on craigslist or facebook market or some such, you can find free stuff that you can flip for profit. This is a crap shoot most of the time and usually requires an investment to get it to sell worthy.

Ive done all these to make ends meet. Hope it helps.

In 2003 I started making websites for my bands, then for my daughters Kindergarten, then for a friends business, I learned so much doing it that after 3 years I was able to get a job as a web frontend developer. And that was my entry to the IT industry I went to university to study computer science and now I work as a Architect and Product Manager of a big system in the automobile industry.

This is location heavy question and it depends a lot on your willingness to do work for cheap, but there are options.

Shitty part time is a great option. Side hustles mean you're free lance and free lance means you do a lot of work finding paying gigs. If it isn't something you enjoy, just find a liquor store or an independent gas station that needs extra hands. They don't make you jump through hoops like corpos do.

If you have access to a lawn mower and a vehicle to move it, lawncare can pay big. My uncle is in his 70s and still makes his living with a beat up rider and a truck. Everything you need to know can be found online and the more you know the better gigs you can get. I've met a few people that started as a side hustle and now do it for a living.

House repair. Paint walls, patch drywall, surface floors, deep clean. It gets you a lot if work especially in renter heavy neighborhoods. Land lords half ass because they don't want to pay for good work, if you offer cheap they keep you on speed dial.

Bit more expensive and technical, but if you have a 3d printer you can make minis and game pieces to sell at local hoby markets. Nerds pay big money for custom minis for d&d and I paid off my $800 printer in a year selling custom hero forge prints. Use abs and learn how to chemical smooth and you'll be the talk of the town.

Ultimately, the best option is to jest get better employment. It's a bitch but if you get creative you can find it.

Waiting tables. Now it's my main hustle.

Crime

In the US? Vote out Republicans