I first got my starts by trying to blog about video games. Then I started a wiki which I bootstrapped off my own saving. Now it produce maybe 20-30 bucks each year. Not a whole lot, but I bootstrap my way with that money in addition to programming work that I started working.
I am hoping to go back in automating the maintenance of my wiki and create new sites in that niche to generate a bigger income, which then will be used to bootstrap other sites.
The way I figure it is that for each domain, I only need to make about 15 bucks to be profitable. Basically, they serve as buffer money used to fund new mini-ventures.