184.108.40.206 - DNS by CloudFlare.
Pi-hole - Can be used as DNS server.
Tenta DNS - Recursive and authoritative DNS server in go, including DNSSEC and DNS-over-TLS.
Trust-DNS - Rust based DNS client, server, and resolver.
AdGuardHome - Network-wide ads & trackers blocking DNS server.
PowerDNS - Sources for the PowerDNS Recursor, the PowerDNS Authoritative Server, and dnsdist (a powerful DNS loadbalancer).
Hello, and welcome to DNS! - Attempts to provide a correct introduction to the Domain Name System as of 2018.