How do these places make money?

I’m going to start a new series here at Jason-Preston.com, and it’s going to be an ongoing work. Whenever I come across something that’s highly successful, but shouldn’t, as far as I can tell, pay the bills, I’m going to post about it. Maybe there’s some key answer that just hasn’t occurred to me yet—feel free to enlighten.

To kick it off?

WordPress. This wonderful system is what I use here to do my blogging. There are no ads on this site, and you know what it costs me to use? Nothing. You know how many ads are on the Wordpress front page? None. This thing is run by a guy named Matt, who, as far as I can tell, shouldn’t be making any money. How does he eat?