Cutting my own hair will earn me at least two million dollars over my lifetime.
This is a specific example, but the same technique can be applied to any savings by using a compounding calculator:
Below are my entries and result. After 80 years, the $12.50 I save per week, (I estimate a haircut is $25 and I would normally get one every two weeks), I will have around 2 million dollars if my rate of return is 7%. The return could be halved and you would still net a million dollars of savings, but historically the inflation adjusted real return has been close to 7%.
The takeaway is it is okay if you are not a millionaire now, you can choose to be one. To be a millionaire almost always requires patience. Ever notice that older people are often the ones walking out of nicer homes? They have simply had more time for compounding to take effect.