Was skimming through Playlist.com: The best iPod-related products of 2005 and saw a link to Senuti. This is a really excellent little (free) Mac OS X application that allows you to look at and retrieve the content from your iPod through an iTunes-like interface. So if you iTunes hard disk goes belly-up you should be able to recreate it from your iPod.
See Senuti (where there are some other nice little apps too). In the Playlist article there’s a link to a Windows app that does the same thing and is also free.