I use a web based remote file-transfer/sharing solution called Synaman from Synametrics Technologies. Synaman is a secure way to send or receive large files without the need for a special client, or all the FTP user setup hassles. You can create accounts for your friends and they too can send or recieve files of any size easily.
Since Synaman is hosted from my dymanic IP web server I needed to make one change to the default notification URL’s it sends out telling you to download or upload. By default Synaman’s download/upload URL has my dynamic outside IP Address embedded in it. This did not work for me as I have seen my IP change several times a day with my current Internet provider. So I want Synaman to embed my dynamic DNS domain in the URL instead.