yoga
my current career (which would have the add-ons of saving more sooner, meeting my spouse earlier, getting to travel more when I was younger, bought a house earlier, etc)
went to the dermatologist to get a diagnosis. I was miserable for years and could have solved the issue much sooner, since she knew exactly what was wrong with me the second she saw me
learned about investing/retirement accounts
Reason #421 for RE: All company calls scheduled at 7am the first day back from a 3 day weekend
I got to attend several calls during the 3 day weekend due to weather spawned emergencies.