(It was only a $10mil buyout offer of a startup I owned 5% of at the time, but we believed we'd be worth 10 times that in a year's time and turned it down. ~8 years later I spent everything I got from the acquisition we got taking a few friends to dinner. (well, "they" by that time - I'd been out for a couple of years but still had my shareholding. Wrong decision in hindsight, but no regrets. I'd make the same choice given the info we had at the time...)

I remember when zuckerberg turned down $1B from yahoo and I couldn’t believe how stupid and greedy he must be to turn that down.