|Seems like a horrible and insecure alternative to VPN tunnels, but whatever. There are plenty of public DDNS services out there. |
No-IP.com's the popular choice.
Dyndns.com was one of the original players, but they've killed their free DDNS service, so they might be hurting and thus unreliable.
OpenDNS offers DNS services, and you could make the records dynamic by setting a low TTL. They're also configured for providing DNS services to businesses, so they should be able to absorb the load and provide "helpful" graphs if they become your primary DNS server.
Check your options with whatever device gets the public IP. That'll determine the services available to you.
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