I run FireDepartment.net (and a few other websites) as a side job because I like helping out with projects I believe in. That said, FireDepartment.net as of today isn't a profitable business and while being a good project, it would be nice if it generated an income for my efforts.
Luckily, the skills and connections I have gained from developing/marketing/iterating this website have let to several jobs (both as an employee and consultant).