Replaced the battery in my Pixel 2, Huawei Watch (1st gen), iPod touch (6th gen), and probably some other things I'm forgetting.
Replaced the fan and thermal paste in my father-in-law's overheating Macbook Pro.
I fixed a design flaw in the charging circuitry in my PowKiddy v90 (handheld gaming device), I wrote about it at https://www.nfriedly.com/techblog/2021-1...
Recently attempted to repair a broken power button in a Moto G6+, but first attempt was unsuccessful. I was at least able to boot it up and recover my friend's photos. Will try the repair again soon.
I also sometimes just pay folks to fix things: my TV, an iPad, lawn mower (required welding), etc. Other times also or give it away for parts/repair. I try my hardest to keep things from going in a landfill.