1. Safety razors - I've got thick growth and I was spending more and more on expensive multi-blade razors trying to find a decent shave without the blade going dull after 3 uses. The answer was to have less, better quality blades rather than the expensive trash in the market. A safety razor multipack costs a pittance and has lasted me over a year. Each blade is 2 sided and can be flipped. And when you're done with it, it can be recycled with no plastic waste. There's literally no down side if you wet shave.

2. Electric screwdriver - it doesn't matter how much DIY you do or how rarely you make IKEA furniture, you still need an electric screwdriver.

3. Brain hacks - your brain and body are predictable physical objects that are programmed a certain way. If you take the time to learn how they work, you can use that to your advantage. e.g. If you know that procrastination isn't a time management problem, but rather an emotional regulation problem about the task that's due; then you can start addressing the cause. Or if you want to build a new habit, you can combine it with something you like, to make you look forward to it (e.g. pick a TV show you really want to watch and only allow yourself to watch it while you're on the treadmill). Or realise that discipline and motivation are finite resources in the day. There's too much info to cover here, but I learn about these things from podacsts mostly:

https://www.drlauriesantos.com/happiness-lab-podcast

https://www.schwab.com/learn/choiceology

https://youarenotsosmart.com/podcast/

https://hiddenbrain.org/

4. "Good enough" tech - You will save a lot of money if you define your use case for tech and then buy a product that is good enough to do the job (and preferably secondhand). I'm currently writing this out on a laptop I bought last week for £150 from eBay, brand new condition Dell, Intel 8th gen i7, 16GB RAM and half TB NVME drive. My gym TV is a £30 IPS Dell monitor with a Fire TV stick.

5. Facebook Marketplace - make a dummy account for a facebook marketplace. I have bought tons of "like new" things in brand new condition (e.g. a whole home weights gym setup) for a fraction of brand new price. Also if there's anything I want to get rid of, then I just post it for sale. I have had a completely worn out, cosmetically destroyed desk that I posted online for £1. Someone came and collected it the same day. It saved me a trip to the junkyard by having someone come collect it and saved the waste by going to someone who will use it. 2nd pro tip: never post anything for free. Scumbag entitled people monitor facebook for free deals and you will have a bad time. Post things for £1 and you'll get serious people who will be grateful.

6. Accept what you can't change - your life will be much better if you stop spending energy pushing against things you can't influence. Traffic cop walking away after giving you a ticket? Accept the hit and walk away. You took a risk not paying for parking, it didn't work out. Go home and tell your spouse about it; then move on with your life.