NameCoin - Namecoin is a distributed domain name system based on the Bitcoin technology.
One Word Domains - Database of all available one-word domains
OpenNIC - An organization of hobbyists who run an alternative DNS network, also provides access to domains not administered by ICANN. People also askWhat is OpenNIC?Which is the fastest DNS server?What is DNS by Comodo?
Domainz.io - Premium domains, for not so premium prices
Freename.io - Web3 Domains and TLDs. Yours, Forever
Undeveloped - Domains you never thought were available