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?
Tool.Domains - Search free to register expired domains
Freename.io - Web3 Domains and TLDs. Yours, Forever
Handshake.org - Decentralized certificate authority and naming