I have realised this is the best course of action for me. I've always wanted to do a startup, do something significant or meaningful. But I also yearn for freedom, like being able to go someplace warm for the worst 3 months of the year. Or just travel for a while. Saving 60% of me and my wife's income and working on side projects will allow me to do exactly that. If none of my side projects take off, we'll still be able to retire by 40. If something takes off then even better, I can keep that going through retirement.
This isn't bad advice, but I'd add one more thing: Have fun today. This doesn't mean blow all your savings on the latest shiny, but be sure to set aside a portion of your money just for having fun.
After all, there's no guarantee there will be a tomorrow, and the prospect of retiring "early" 10 years from now does remarkably little to make you happy today.
