Apple iPod = Portable USB Flash Pen Drive + MP3 Player
You have plenty of free portable hard drive space on an iPod that needs to be filled with something other than music. Fortunately, iPods can be used a Portable Hard Drive that can be plugged into the USB port of any computer.
So not just music, iPods can store or transfer pictures, video clips, PDF files, Word documents, Excel Spreadsheets or virtually any other file format you wouldn't ever listen to or watch on your iPod.
Jake has a simple guide on How to Use Your iPod as a Hard Drive
First connect it to your computer using the sync cable. Bypass the iTunes interface and expand My Computer. You should see your iPod in the list of available drives.
Either copy files into the root directory of your iPod or create a folder in the iPod directory structure to store your transported files.
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