I have two project which make zero money but I love doing them. I learn so much from writing code for them and use them as a playground to try out and apply new technology in a production environment, Yes, they are production environment because they are severving real customer, just that no one pays me so far.

https://noty.im An uptime monitoring tool

https://betterdev.link a news letter and from there, I spin up a link sharing service https://one.betterdev.link with full text search for content of link as well.