"WHENEVER I DISCUSS the dynamics of the open-source
community, someone inevitably asks, "Who pays the salaries for all
of this software development? How can these programmers survive by
writing free software?"
A few open-source programmers are fortunate to have jobs writing
open-source code full-time. Others have jobs where enlightened
employers allow them to work on particular open-source projects
part-time because the company benefits from advances in these
projects. Still, others enjoy consulting on open-source projects
Nonetheless, I believe most open-source programmers do not make
their living by writing open-source code. Many are professional
programmers, consultants, and (ahem) journalists by day, and
open-source developers by night."