I been giving this question a lot of thought: “What makes an entrepreneur different from an employee?” In my not so humble opinion it’s only two things, money and cast iron balls. The entrepreneur has some amount of each, in fact everyone has some amount of each. It seems these things are multiplicative, you can be successful if you have a lot of money, or if you have a lot of balls. It’s good to have a lot of both. I believe there is a threshold above which entrepreneurs operate. Employees simply don’t have the required combination of balls and money. It’s a simple equation.
(Balls)*(Money) >= Threshold

On a related tangent, I believe that this threshold can change, and that people can change. Someone who might start out an employee can become an entrepreneur later in life, or even do so concurrently in different parts of their lives (hence all the microISVs out there).

With this formula in mind, the implication is that anyone can be an entrepreneur, even the very poor, as long as they are willing to take risks. Also, it implies that you can grow your risk tolerance, possibly through taking more and more risk as you get bigger and bigger opportunities. It seems the people who would be best at attacking this problem through sheer balls would be the people who have the least amount to lose, or basically people who have just graduated from college and have yet take on large fiscal responsibilities, as suggested by Paul Graham.

Long story short, Nike was right, Just Do It.