I downloaded it, and it was able to hook directly into the Dynamic DNS Network Services site and update my account based on whatever IP address I was running on. Of course each answer begs a new question. Here's where it gets trickier. Dynamic DNS Network Services doesn't provide actual DNS hosting or domain aliasing services. Seems like someone should.
Granite Canyon has a free public DNS service.
Unfortunately, their form leaves a little something to be desired in the way of usability. You have to manually enter all the technical DNS info. I didn't get all the way through it. I've been waiting for the opportunity to run my own server and be able to really dig into the guts and customize things. If anyone knows anything about DNS, I'd love to get a little help setting up one of my domains to point to my home machine.