Earlier quoted context omitted.
I'm in my 30's, married, have a son, and a mortgage. But I also have enough savings to pay off my mortgage in full today if it was an urgent need.
... how? Either your mortgage is very small, or you have somehow managed to save an incredible amount of money. It's really the latter that I'd like to know more about.
As I mentioned in the other comment, my savings rate has been trending upward for a while, and I now save about ~40-45% of my take-home pay.
But, even when I lived in the bay area, earned less money, and paid twice my current mortgage in rent, I was still saving ~15% of my income.
I don't consider myself deprived: we eat out, buy fancy phones, etc. We have a separate bank account just for giving that gets some money automatically transferred in each month. Our car is a 15-year-old civic that looks terible, but we don't drive that much and it still runs great. We'll probably replace it soon, but I kind of want to see how long it will go at this point ;)
Like I mentioned in my other comment, http://www.mrmoneymustache.com/ has a lot of great advice. There's a few sites like that one, but MMM is my favorite.