Here on Xbox.com when I go to the new security page.
I click on Require your Windows Live ID password to sign into Xbox Live.
But the link isn't working.
If you have more than one Xbox 360 console or you want to play games at a friend’s house, you can download your Xbox LIVE profile or gamertag to multiple consoles. For security purposes, we recommend you password protect your Xbox LIVE profile so no one can sign in using your profile.