Parker Moore and I (along with many contributors) have been spending quite a bit of time on Jekyll recently. Over the last 30 days we've merged 17 pull requests and closed 62 issues. We're ramping up for a 1.0 release and there's a brand new website in the works. You can check it all out on the master branch.
Tens (or possibly hundreds) of thousands of people use Jekyll now. It's interesting to note that Jekyll started out as a "brain fart" as well. Just one amongst hundreds of blog engines. I wrote it because I was dissatisfied with everything on the market, and I thought I could do something different and better, to serve my own needs. I open sourced it, because I thought others might get a kick out of it.
I'd wager that most of the great things we use today started as nearly ephemeral emanations from someone's mind, often late at night, or helped along by a snifter of brandy. The funny thing is, if you never try out your crazy ideas, you'll never know which ones might have changed the world.