Early Retirement : Monthly Income Sources

I am very interested in developing passive income sources to meet my monthly expense needs.  Currently we are stuck in the economic rat race, with all of our monthly income coming in from our salaries.  We have no other sources of income (other than some small interest earnings from our savings bank accounts; which I actively try to minimize, since I am not interested in accumulating any debt income)  We also get some dividend income from stocks, but that is too small at this time to make any significant impact to our overall income profile.  We do not have any rental income either.  So my Oct'2011 snapshot of monthly income sources, looks as follows:

Now this is a pretty depressing picture to look at from an early retirement perspective.  Ideally I want the bulk of my monthly income coming in from non-salary sources.  At this time we are 100% locked in to our jobs since we are completely dependent on our salaries for monthly expenses.  Over time, I will need to come up with additional income sources to first supplement, and then replace our current salary based monthly income.