I was wikiHow's first (I think) intern. Back in 08 their entire company was two guys working in a side room in Jack's dad's office and only one tech guy who was based in Toronto.
I don't think that wikiHow was bootstrapped in the traditional sense as I'm pretty sure his family has a decent amount of money (or whatever passes for that in the Bay Area these days). That being said, here's a guy who's passionate about what he's doing and is comfortable avoiding the start-up rat race. Given all that, the numbers he's pulling are pretty remarkable.