When you're running multiple services you want to receive a message when something goes down. Not just sites, but also backends and cronjobs deserve to report warnings on failures. To deal with this, there's a service called Better Uptime that we've come to like very much for this. Not only does it offer a generous free tier, incident reporting, on-call settings and a clean user interface, they also allow you to create status pages.
Here's the status page for dearme.email, just to give an example.
There are many similar services out there, but for our stack, we've come to really appreciate the simplicity of the tool, which is why we deem it software worth paying money for.