If you build it, they will rumble.

I think I've mentioned that Mike is an economist. He's fond of saying stuff like "supply and demand" and "the law of diminishing returns" and "cost-benefit analysis" and "niche market." I asked him what that last one means and he said it's when there's a narrow but noticeable demand for a specialized good or service. It doesn't have to be something brand new, he explained. It can be a new twist on something that's already out there, but that fills a particular need for a subset of its consumers. I wonder if this qualifies: