I have a great 20gb 4th Gen iPod that I use for voice memos mostly, some music on it. It is just about to run out of warranty and I want to get a new battery (it's needed it for a year) and have the hard drive checked. Can someone tell me how I make sure I have everything off the iPod backed up on the three Macs I own? Do I have to reinstall the iPod CD or something? Is there a two mac limit? I can't believe I'm asking this, but I really don't understand how this works, after being a mac person for so long.