The only cost is the domain name, it's small enough to add to my existing hosting.
With legacy in mind, I wouldn't mind support the domain cost, if you so allow. The feeling of intrigue that occurs when a (new)user randomly encounters this link is more than worth it.
I've been thinking about Njalla since nullius mentioned it years ago (...)
My only setback with Njalla - which seems to get some of their domains from Tucows[1] - was the one that I mentioned before:
What separates Njalla from traditional domain name registration services?
We're not actually a domain name registration service, we're a customer to these. We sit in between the domain name registration service and you, acting as a privacy shield.
When you purchase a domain name through Njalla, we own it for you. However, the agreement between us grants you full usage rights to the domain. Whenever you want to, you can transfer the ownership to yourself or some other party.
This is also complemented in their TOS (which took a while for me to find in their website[2]):
9. Term
9.2 1337 may in its sole discretion, also terminate the Services and these Terms and choose to keep, suspend or cancel your domain name registration if:
you breach the obligations under section 4.2 above;
you fail to provide payment in due time or accurate contact information as requested under section 3.1;
required by ICANN or any other registry operator;
needed to comply with any applicable laws, government rules, requests of law enforcement, court orders or public authorities;
it is in compliance with any dispute resolution process;
to avoid any potential civil or criminal liability; or
your use of the Services in any other way incurs damage on the Services or 1337 or entails a risk thereof.
9.3 Further to the above, 1337 is entitled to suspend or terminate all or part of the Services where necessary due to technical reasons.
9.4 In all cases where 1337 is entitled to terminate the Terms with immediate effect, 1337 shall also be entitled to discontinue the Services with immediate effect.
Additionally, their TrustPilot reviews[3] (which we have to take with a grain of salt), aren't looking good as well. But, once again, we don't know what type of services were this users hosting, we can only speculate.
So, to sum it up, they pretty much control everything, so if something happens in the future, you may lose access to your domain without any chance for a discussion or anything related. I guess backups would be your best friends in this scenario...
There's another option, maybe you're interested: IncogNET.io. I've read about it on Lowendtalk.com, it's owned by someone named "MannDude" there. I think Njalla has been around longer, but those are the only two providers I've found that don't ask for any information.
I honestly had never found references to that service, I will definitely look it up. The website loads a little slow for me, but probably it's due to my internet. In my quick search I wasn't able to find a lot of references to the service (other than some small Reddit threads) but I'll explore it better. It's a shame that the two services that I would definitely use (Youtube and Reddit proxy) are down[4] at the moment.
[1]
https://njal.la/blog/hijack/[2]
https://njal.la/tos/[3]
https://uk.trustpilot.com/review/njal.la[4]
https://incognet.io/privacyprojects