It's tempting to just write a comic called 'Everyone Mail Randall Munroe Twenty Bucks' - maybe it would work, and I could just close down the 'xkcd' store and sit on a beach and draw pictures and make snarky Reddit posts for the rest of my life.
I used to work at NASA in Virginia. It was nothing glamorous; I was just tasked with making code compile for obscure projects, and I wasn't very good at it. Now I spend most of my time drawing pictures and looking at funny things on the Internet, which in retrospect is largely what I did at my old job, too.
Google owns YouTube, and recently, I drew a comic about an idea for a YouTube feature - which they actually took seriously and implemented. So I'm thinking that maybe we'll have a future where Google is 'xkcd.'
I don't have hard numbers about this, but the impression I get is that the amount of eyeballs you get from being on the humor shelf at Barnes & Noble - it is almost insignificant.
I learned very early on in life that not everyone wants to hear every fact in the world, even if you want to tell them everything you've ever read.
I think the comic that's gotten me the most feedback is actually the one about the stoplights. Noticing when the stoplights are in sync, or calculating the length of your strides between floor tiles - normal people notice that kind of stuff, but a certain kind of person will do some calculations.
What people don't appreciate, when they picture Terminator-style automatons striding triumphantly across a mountain of human skulls, is how hard it is to keep your footing on something as unstable as a mountain of human skulls. Most humans probably couldn't manage it, and they've had a lifetime of practice at walking without falling over.
I think the really cool and compelling thing about math and physics is that it opens up entry to all these hypotheticals - or at least, it gives you the language to talk about them. But at the same time, if a scenario is completely disconnected from reality, it's not all that interesting.
One of the things I've learned with doing 'xkcd' is that you sort of give people, 'Here's the thing, and here's the button you can press to get another thing.' Sometimes that can be more easy to digest than, 'Here's a long page of things.'
Once I got married, I started working from an office. I found that having somewhere to go that isn't my house is mentally helpful: 'This is the place where I answer email and write blog posts,' and 'over there is the place where I do the dishes.'