A few day ago, I was introduced to xip.io.
TLDR; You can have hostname for any IP Address!
$ dig +short @ipname.me www.192-168-1-1-ipname.me 192.168.1.1
It uses the powerdns pipe backend to run a (187 lines) bash script, that strips the IP from the hostname and returns the IP. This works so well, that a few services depends on xip!
The project is here: ipname on github
But not only returns you an IP Address for any (dynamic) hostname you ask, but you can also use this free & public service as a what-is-my-ip project over DNS.
$ dig +short @ipname.me googleyahoo.com 18.104.22.168
PS The code also validates the IPv4 Addresses!