A few months ago, I put a note on the listings for the selvage bath mats in my Etsy store that they are available for custom order if someone wants a different size.
One person asked about an 8 x 10. As in 8 x 10 FEET. Good heavens. That would be a formidable project. Also formidable in price (they're 14 cents per square inch, you do the math on an 8 x 10 project and you'll see what I mean.) I haven't heard back from that customer, I assume they're spending their money on something more sensible, like their mortgage.
But some people are far more sensible. Like Gina from Virginia, who asked if I could make one in a 24" square.
Gina said it's for her kid's bathroom. I hope they like it!