No-IP - Dynamic DNS and Managed DNS Provider
FreeDNS by Afraid.org - Free DNS hosting, lets you fully manage your own domain. Dynamic DNS and Static DNS services available. You may also create hosts off other domains that we host upon the domain owners consent, we have several domains to choose from!
Duck DNS - Free dynamic DNS hosted on Amazon VPC
ClouDNS - ClouDNS is a platform that allows users to keep their websites, data, and network security all the time.
Dyn - Managed DNS, Outsourced DNS & Anycast DNS
OpenDNS - OpenDNS provides faster and safer Internet access for your home or Business.