From PGH Design:
This program will sit in your system tray and monitor any IP address changes, and when such occurs, it will e-mail you the new IP address to the e-mail you specify. Very useful for people running remote access software such as PC Anywhere, or VNC on their home or work computers with dynamic ip addresses that typically only change once every few to several days. You can specify the time interval for the check and the recipients email address. Works through routers and with any mail service supporting smtp.