The iPod is a great music player, but one of the potential flaws is you are supposed to only use iTunes in order to add music to your iPod. For many people, it is not a big deal that you must use iTunes, but iTunes does have limitations. It is possible to add music to an iPod without iTunes by using other software that could offer more freedom.
Set up your iPod to act as an external hard drive. Select the iPod on the iTunes source list after connecting the iPod to your computer. Open the iPod preferences window by clicking the "Options" button in the iTunes window and click the "Enable disk use" option.
Download Floola from floola.com. Floola is a free program that will allow you manage your iPod from any computer by running software off of your iPod. It is supported on Linux, Mac OS X and Windows.
Install Floola by dragging the application to the iPod and running the application from your iPod. That is all it takes, and if you want to uninstall, simply delete the application.
Add music by opening Floola off of your iPod, clicking on the "Item" menu and selecting "Add." You can now drag music from your computer into the box that opens and click "Add" to copy your music to your iPod. You can also expand the "Advanced" options to choose what playlist your song is copied into.
Close Floola, eject your iPod and listen to your music. Be sure you eject your iPod before you disconnect it from your computer. You can hold "Shift" when you close Floola to automatically eject your iPod.
Floola can also sync video with your iPod if you have an iPod that has video playback capability. Floola is compatible with multiple operating systems with only one install. So once you install Floola on your iPod, you can plug that same iPod into multiple computers running different operating systems and it should still function.