Well in my case the answer would be "because I'm bored" (though I actually have a laptop at work, and a desktop at home, So I'm playing games with a company-iss

Well in my case the answer would be "because I'm bored" (though I actually have a laptop at work, and a desktop at home, So I'm playing games with a company-issued laptop in my office). But there are plenty of developers (on HN in particular) for home "their machine" isn't just something that is in their office for work use, but is what they have for personal use as well (maybe they're freelance, maybe they work for their own startup, whatever).