1) Security: is it possible for anyone to hack into my ATV as it is on my network but not protected by any firewall? 2) What are the best video settings for HD on a 1080p TV? RGB High? I thought I saw AUTO as an option the first time I was in the menu but its not there now 3) Does anyone use their ATV as a backup for Music and other content purchased on the Store? If I for some reason lost my music on my iMac, could I retrieve it from the ATV? 4) Can the ATV be used as an external hard-drive?