The trick here is that this can be a value (rrdata) for NS records ;) Or CNAME rrdata. Or MX rrdata. Albeit, there is little point in using it this way, as opp

The trick here is that this can be a value (rrdata) for NS records ;) Or CNAME rrdata. Or MX rrdata. Albeit, there is little point in using it this way, as oppose to just add A record in your own domain anyway... For people without a domain and a static IP, this may be useful too too publish a page, and possibly obtaining ACME tls cert.