[csp256]

It is entirely possibly to retire at 40 earning $200k (~ $139k net). If you spend $60k a year (I live in Sunnyvale and spend $30k a year) then you have a savings rate of a bit over 55%. A 55% savings rate has an expected time to financial independence of 14.5 years.

You could easily be a multimillionaire by 40 with those numbers. If you spent as much as me it would take about 6 years.

[speedplane]

I don't disagree with your numbers, many people live on $30k/year by necessity. But if you do so by choice, you'll have to give up quite a bit. You won't be able to engage in much of the social activities that others enjoy in your 20s and 30s. And while it's possible (even easy) to live on $30k/yr in your early 20s, as you get towards your 30s, you'll start feeling quite a bit of social pressure from your peers to conform to a more expensive lifestyle.

So if you're willing to buck society and sacrifice some of the best years of your life, just to sit on a million dollars at the age of 40, then go ahead. But if you are willing to buck society and sacrifice so many luxuries, why do you care about money at all?