I stumbled upon freenom.com, which offers free DNS domain names. So I tested it and successfully registered drjohnstechtalk.ml. .ml is Mali’s top level domain. I’ve heard it’s the only African country to open up its domains for free registration. There are a few other choices like .tk and .gq which are even more obscure.
As far as I can see this is a no strings service. It’s possible that they will share your registration data with third parties, but I don’t think this is the case since freenom is from the Netherlands where privacy tends to be stricter than in the US.
Creating an address record is easy enough, but no other kind of resource record seems available to free users. That can be pretty limiting.
References and related
www.freenom.com. In the search field just put the domain name without the extension, e.g., drjohnstechalk. It will tell you which extensions are available for free.
How about putting a free certificate on your free domain? Let’s Encrypt makes it possible.