I love this article just because so many commenters hate it. I really like the super niche side-projects -- I ran an analytics site for minor league football, built with a couple of Ruby scripts and a free Netlify plan. Was featured on ESPN, famous NFL twitter accounts, and did a million pageviews in 2 months.

I licensed the data to a fantasy football site and it was starting to make money before the league shut down.

The stakes are so low that it's really worth giving it a go.