I just realized I am technically a Millionaire - although I dont feel like one. But here is how i "did" it.
I have never been a big spender, so i never had any real debt, and i pay off everything each month because i can't stand to pay interest. I expect I got this from my parents who also have no debt and never have. Everythig was paid for at the end of the month or in cash, including college and the like. I also remember one thing when I go to buy something - "you earn it once and you spend it once".
Even when young, I had a bank account. i have no idea if it was my idea or my parents for me to have one, but each week i earned $2 babysitting after school for one of the neighbors. Gave her a little time on her own. $1 each week went into that bank account. I am not sure what I did with the other $. Any other money that came in went into the bank account, but in a family where you NEVER give money as a gift, it was not much. However, the interest rate was high, and the money added up, which allowed me to understand quickly the value of compound interest, even if i did not know those words.
So I was already off to a good start. I loved seeing my bank account grow monthly. After college I got a job and only rented a place I could actually afford. I drove the same car for 8 years, until it was hit by another car and could not recover. My parents gave me that car in college, and I never had a car payment. Then I made a mistake - I fell into the leasing trap and had a terrific car I loved, but it was leased, and when the lease came off I had no car, and no money. So I learned from that one, and bought a second hand car, cash, which I used my emergency fund for, not a series of wise decisions in retrospect, but it worked out for me. I still drive that car, its a 1991 Maxima, and going strong. Although I am putting some money aside for when I will need to replace it, which I think may be in the next year. Likely I'll buy another used car if I can find a good one. My emergency fund is again fully funded (and has been for many years).
As my income has gone up over the years, much of the additional income has gone into savings, and I have always fully funded my 401K and the like. With the terrific market up to 2007-2008, that money just kept growing. Even with the market correction, I realized I had quite a bit of money, over 500K, and under 40, and with no debt. Then I lost my job. And it took 8 months to find another one. But I did not have to go into my savings as I had no debt, quickly gave up my rented apartment and moved into the house I bought when the real estate market crashed, in both cash (mine) and with a family funded mortgage. The house was intended to be a weekend summer house, but it was fine to move into when I needed to. The family funded mortgage actually has an interest rate of 4%, high now, but at the time reasonable, and it keeps the money in the family, which is a win win.
So now the markets are going back up, I am working again, and recently put my information into mint.com, which is when I realized I have a net worth, in cash and house of 1.2 million. And that does not include car, furniture, electronics and the like. So im the millionaire next door, without even knowing it. And all because I was able to understand saving at an early age, and paying for things I could actually afford.