WinIP
WinIP is an easy-to-use update client for Windows. WinIP features an intuitive graphical user interface that makes it simple to keep your dynamic DNS records up-to-date. The latest release is 4.1 from April 2012. Features include:
Perl
dnsmax.pl is a text-based dynamic DNS update client for Linux, FreeBSD, Mac OS X, and any other operating system with Perl support.