Professionally, around 1978 I had an epiphany: I realized that I was sometimes very good/lucky at solving ‘show stopper’ type problems at work, and I 99% freed myself from worrying about my job. I started a hard policy of working just 32 hours a week (taking 80% salary) and prioritized learning things that I cared about. I also became more generous in putting energy into helping coworkers; I have had 6 visits this year from old co-workers (I live off the beaten path in Sedona Arizona) so I don’t feel like I am just bragging when I say I have respected coworkers and cared about them.
So really, my life’s work is learning what I want to learn in tech and spirituality (mostly Self Realization Fellowship and also Buddhism).
EDIT: I forgot the ‘big thing’: I love my family and friends.