I just hit the $1M mark about a week ago, with a combination of assets (IRA, 401k, index funds - mostly VTSAX, a few stocks, some cash). It's weird to log into Personal Capital and see that number sitting there. I thought it would feel different, like "holy crap I'm finally a millionaire" but I don't really feel much, aside from feeling a lot more financially stable than I expected to at age 41, especially considering 10 years ago I was in a situation where I was grateful to have my car totaled (but still drive-able) in an accident where I was not at fault, as that 3K insurance money kept me from going into debt due to financial issues. I haven't told anyone about hitting $1M (and not that many people even know I am pursuing FIRE). I don't really have anyone that can relate to it, it's nice to be able to log in here (first time on the forums in 3 years, in fact) to share.
My original numbers for FI were $675K (my lowball number in case I really hated my job and wanted to live pretty lean), then $750K (based on what I generally spend in a year, with this number at 4% withdrawal I could continue in the same lifestyle), and then $1M as a stretch goal. Well, I made it. My tentative plan is to pull the trigger on quitting my job at the end of September, right after I return from a 2 week vacation (and after some stock vests in September as well).