dyndns.org
dynu.com
easydns.com
+ enom.com
+ entrydns.net
freedns.afraid.org
namecheap.com
no-ip.com
+ nsupdate.info
+ opendns.com
ovh.com
regfish.com
selfhost.de
udmedia.de
variomedia.de
zoneedit.com
+
+Also supports DNS updates via the ISC BIND nsupdate utility.