Third world networkers - how to disable annoying Itunes backup on windows

Locate your iTunesPrefs.xml file.

It’s usually located in C:\Documents and Settings\username\Application Data\Apple Computer\iTunes or C:\Documents and Settings\username\Local Settings\Application Data\Apple Computer\iTunes.

make sure that hidden files are visible in the Windows Explorer
  
Backup your iTunesPrefs.xml file
    Open iTunesPrefs.xml using a capable text-editor (e.g. Notepad++, Ultraedit, but not MS Notepad)
    Search for a section called User Preferences and paste the following snippet into the User Preferences Section after the first :

    DeviceBackupsDisabled
   
    dHJ1ZQ==
   

     Save the file and restart iTunes. Backups should now be disabled. 
To enable backups again delete the XML Snippet from iTunesPrefs.xml file.