I was a consultant at the time, and wanted to point out how crappy my client's webhosting was (really I just wanted to convince them they were going offline long enough that spending an extra $50 per month on a proper wordpress host would actually make them money)
I kept a twitter thread of all the features I was adding (https://twitter.com/RozenMD/status/1364881512500404224), and eventually it spread via word of mouth. It doesn't make life-changing money, but I could see myself running the service full time eventually.
I ended up moving off of 100% serverless compute, since enough people were using it constantly that it was 80% cheaper to run several servers 24/7.
It's also an interesting model that you either waste $19/month on something that gives no alerts or waste $50/month on unnecessary hosting. Or do neither and waste lots more money on lost customers.
The alternative is being alerted by emails or phone calls from prospective customers asking if they're still in business - a very awkward phone call to be on!
Took a few hundred hours to implement, we got pretty lucky to find an audience, and it’s too a year or two after making it free to actually start getting recommended by the App Store - I think we must’ve crossed some threshold for getting enough positive reviews, or something. Anyways, I can’t say it’s a reliable way to make money, but I had fun doing it, and it does bring in some money.
Brings in about $100 MRR split between 2 people.
It's been surprisingly successful with other B2B startups.
Not enough revenue to be my main source of income, but it's a nice monthly bonus.