One Word Domains - Database of all available one-word domains
Domainz.io - Premium domains, for not so premium prices
Handshake.org - Decentralized certificate authority and naming
DomainWatch - Domain Monitoring Made Easy
NameMing - Get smart domain name suggestions using synonyms, suffixes, prefixes, short url, new gtlds to find the perfect domain name. Generate ideas for social user names and check availability for free!
domdb - Park your domain in less than 15 seconds