What is the best way to earn passive income?

After reading Rich Dad, Poor Dad and embarking on a few ventures including buying a rental property, designing a board game, and joining www.ytbinterest.com, I find myself looking for more opportunities. What other opportunities for passive income are out there ?
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High yield money market accounts pay around 5% interest these days.
I like to let my money just sit there and earn me more money.
Sell your junk on Ebay.
Buy a house if you can in a fast growing area, you will double your money.
Sounds like you are on the right track. I can tell you about my business as well as recommend some more books for you to read on the subject. I like that you are open to alternate streams of income and taking advice from the people who are highly successful like Robert Kyosaki. Good things are in store for you!