Unexpected acts of kindness from strangers you don't ever forget:
As a snot-nosed kid just starting out building electronic things, I tried to tackle a rather ambitious (and expensive for me) project. The damn thing didn't work. In fact, it turned electricity into smoke and some components even went bang! Eventually, after dog-earing the Yellow Pages, phoning around unsuccessfully for assistance, I came across a bloke at "Roake-Barefoot Electronics" who offered to have a quick look at it.
I pedalled around 30km on my bicycle to his shop. Despite him having his own work piled up high, without saying a word, began fixing it, unsoldering all the components and replacing the buggered ones. It took almost a whole afternoon of his precious time.
Handing it back to me in a working condition and with a totally deadpan expression on his face, just said, "No charge. Just don't do it again." (It turns out I had managed to solder the components to the wrong side of the PCB so everything was basically reversed 🤦♂️😂)