> One day, on a plane with WiFi before paying, I noticed that DNS queries were still allowed and thought it would be nice to chat with an LLM over it.

There used to be a service where DNS requests to FOO.that-service.org would return the abstract for the Wikipedia article "FOO".

edit: I think it was this one, seems to be defunct now: https://dgl.cx/2008/10/wikipedia-summary-dns