When the unvested stock options (ISOs) I had went from making me a paper millionaire to a pauper overnight. That was just the start because I was working for a top-tier dot-com firm. I was very lucky. I sold most of what I had for a down payment on a house in March 2000, just as the bubble was bursting. I didn't fully cash out. It took a bit for my 401k to recover.

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