I also did some research for you windows users. I found a site that also has the disable backup program as well....

Dennis Nederlof wrote..... I have written a small FREE Windows program called “iPhone Backup Switch”. The program will allow you to enable and disable the iPhone backup feature in iTunes. I have tested it pretty well in Windows XP and VISTA. There is a backup feature that will backup the iTunes configuration and let you restore a previous version, if something goes wrong. Comes complete with installer and uninstaller.



Get it here:
iPhone Backup Switch