www.Yi.org also does dynamic hosting. I’ve been using it for a while. The best part is you can use a program or a web interface to update the IP address. I use a windows program on my desktop at home to update called yiPost. The funny thing is, it’s my linux firewall that runs on the IP even though it’s a completely different computer the runs the program. I can provide more info if required, but the website is pretty good.