I have not. While I am intrigued with the possibility of making online income, it seems to be less passive then how I want to spend my time. Regarding your blog / site, you have done quite well for yourself. However, you have to keep pumping out content or your site would eventually go out of business. That sounds like more of a commitment then I would want. Regarding your book sales, it is probably relatively passive now, but certainly was not when you were writing the book. Now if you love it, great. Just not for me.
You can easily make it ‘customizable’ by creating a few different variations of the project. I’ve sold a customized personal investment plan on the site and deliver one of four different plans depending on the answers to questions sent by buyers. It involves almost no work after you’ve created the project so it’s an excellent source of residual profits.
Once your audience has grown and you have validation that you’re offering them value, there are many ways to create passive income. You could sell digital products like ebooks or courses, take up affiliate marketing in which you promote other company’s products and earn a commission when you sell that item to your audience, build a community and charge people to be a part of it, create software and sell that, among other avenues. Ask your audience directly what would serve them best, or look at what they’re saying on Twitter, Facebook or other websites, to find out what problems they have and how you could help solve them.
Managerial accounting defines residual income in a corporate setting as the amount of leftover operating profit after all costs of capital used to generate the revenues have been paid. It is also considered the company's net operating income or the amount of profit that exceed its required rate of return. Residual income is normally used to assess the performance of a capital investment, team, department or business unit.