1. Saw an ad in 1980 for a Radio Shack TRS-80 for $499. Suddenly understood that computers were more real than the spinning tape reels shown in movies. Started learning BASIC at the local Radio Shack while my mom was grocery shopping next door. Got offered programming jobs at least twice during those sessions (or maybe they were child predators). I've been exchanging code for money for the 40+ years since.
2. Around the same time, age 10 or so, I was in a situation where I should have been killed or badly injured. Instead, a car suddenly appeared and instantly killed the thing that was trying to kill me. The car didn't stop; it kept driving, leaving me alone on a country road with bloody flesh (not mine) sprayed 20 feet around me. Since then, though I'm not religious or very spiritual, I've felt special, as if my life is meant to achieve some purpose on Earth. That memory motivates me when I'm feeling aimless or down.
3. The first time I attended Burning Man. The first time I experienced the kindness of strangers as the rule rather than the exception. That inversion in my default assumptions about other people has made an enormous difference (and undoubtedly has helped shrink the giant chip I have on my own shoulder).