Passive Income

So to clarify...I do not have the typical 9-5 job, (does anyone really?).
I own some investment properties, I manage some investment properties, and I do some real estate. I have been through enough career changes to know that I have to have some "passive" income.

I found a pretty good blog that offers some ways of learning more about passive income:
http://www.lifeoptimizer.org/2008/02/18/free-passive-income-resources/

I enjoyed Five Ways to Create Passive Income With Little or No Money

I am open to suggestions. If you type in"ways to make passive income" into any search engine, you are most likely to come up with tons of opportunities.

Please share. We all want to learn ways to earn money!!