Question for iPod users:
Does the iPod software allow you to store your music files on either the PC, the iPod, or both at the same time?
~OR~
Does it have some kind of system where you have to "check out" the file to the iPod, and then it\'s not available on the PC while it\'s on the iPod?
I seem to remember hearing about such a system on some piece of hardware, and I don\'t remember if it was the iPod or something else.