Updated: May 3rd, 2010
I'd like to pose this question to all WordPress developers – plugin, theme, as well as core ones:
How do you make your living?
And, for clarification, by this I mean: "what are your primary sources of income?"
Open source is a beautiful concept but it often comes with a price tag or, rather, the inverse price tag: most of the time you are not being paid for your time (of course, there are exceptions, such as companies hiring dedicated open source developers and keeping them on their direct payroll).
Everyone has to make a living, however, and everyone has their ways.
Developers can benefit from such income sources as: