I recently heard a great quote about the mythical beast of online passive income...
"I work 16 hours a day, so I can earn money while I sleep!"
Some days feel like that, a lot more so when starting out.
Now, however, all but one of my affiliate websites are what I consider highly passive... meaning I can run them and maintain current levels of income on less than 1 hour a week (total for all sites).
If I want to grow income, I'd be up in the 4 - 6 hour / week range.