Asklemmy

• A pinecil. It was like $30, and has paid for itself within the first two things I did with it (repaired a good computer mouse which just had a USB connector lift from the board, and fashioned a DIY solar connector). I have repaired/made countless other small things in the few years I've owned it.
• Our bicycles, I guess? Financially speaking, they were dirt cheap (~$80 for both), we've sold our Prius since we bought them ($5000), we're not paying for gas for trips within the city (~$30/mo), we're not paying insurance or parking or maintenance or any of that crap (~$20-30/mo or so). So they have paid off within the first couple of weeks. And there's so much more: both of us lost some weight, city errands are sometimes faster, and usually more pleasant now (no being stuck in traffic ever), and we're not wasting space on a useless hunk of metal or polluting the air we breathe.

• Beefy Laptop
• Rechargeable tools (especially the Impact Driver)
• Local library membership

Leatherman. Spent like $140 on a good one (Signal) and it was used nearly every day. Pliers, screwdriver, pry, cut, etc. Great to have easily available on the hip.

I'd bet that selfhosting jellyfin and running sunshine/moonlight has saved me close to $800 on comparable services since I learned to do it last year. So I'd have to say my GPU, which is used mostly for those purposes.

My robot vacuum! My robot vacuum with the little home dock tower thing that lets it dump its load and keep vacuuming! I had the original robot vacuums that didn't have a dock to dump their garbage in and it helped some but mostly it needed to be cleaned more often than I would have vacuumed my house without it, the newer ones with big receptacles are so worth it, once a week I dump his container and change his filters and maybe give him a little wipe down with a dust rag and he's happy as a clam. I bought a set of replacement filters so that I can take the old filters out and use my big vacuum on them to get most of the dust and then chuck them in the washing machine, once they're clean they go in the filter drawer and I just rotate filters once a week.

Stainless steel cookware. Spend the extra money to avoid shitty non-stick and aluminum. Steel heats evenly and maintains temperature. My food has improved a lot just with this change

Related: a good knife. Get a good santoku and you'll be prepared for the vast majority of kitchen tasks.

A slipping torque wrench, two jack stands, and a hydraulic jack. I change the summer and winter tires on several cars twice/year and have been since the 90s

When Germany first came up with the idea of subsidising electric cars, we were able to snatch an electric golf for about 20k€. We're commuting a lot, making roughly 25k km per year on each car.

When we were using our regular electricity provider, we reduced our monthly gas bill from more than 300 € to less than 100 € for the golf. Since we switched to a contract that is bound to stock market prices, we lowered it to less than 40. Saving about 270 € per month now.

Factoring in about 500 € of taxes saved each year and between 1000 and 2000 Euros worth of repairs for our old combustion engine cars per year, the car already paid for itself and saves us money.

Any gadget/tool/product with standard AA/AAA C/D sized batteries and a bunch of rechargeable batteries. Mostly, if I leave a gadget is because it doesn't work, or because the included rechargeable battery is depleted and hard to replace.

A comb binder for bookmaking.

I print off a lot of RPG books and music that would otherwise cost a fortune. Now it's basically the cost of toner and paper.

I like having an e-reader for most stuff, but some things are just better as physical objects that can be marked up and tabbed.

Bicycle for sure. I'm going to get one fitted for winter and hopefully be able to use either depending on weather all year round going forward.

Dishwasher. It might not have paid for itself in money but in peace of mind - how I hate doing dishes. It ruins my day and stresses me out, so not having to deal with it has been truly valuable.

Hiking boots. They're meant for summer hiking but I use them all season, but with studs in winter. Have saved my ankles and feet from twisting, blisters, heat and cold.

My Sodastream has saved me a lot of money—with some cheap syrups I just make very inexpensive nice drinks. Especially considering I got mine second-hand and refill it through a local guy who fills the cylinders for half the price. I suppose I could save even more money if I figure out how to refill the cylinders myself.

While it hasn't paid for itself yet literally, getting a hybrid electric/gas car has been amazing. I only fill up roughly once a month and it costs ~$20. I've already had it 6 years and the only thing I've had to do is bring it in for the occasional recall notice for system updates.