How to Organize Videos on Your Hard Disks

To organize videos on your hard disks seems like a simple thing. At least it is as long as the amount of video and available space stays within limits... If your stuff does not fit on one hard disk anymore, things start to get a little bit more complicated and duplicates are harder to avoid. Also general questions concerning the organization arise; how should the videos be grouped, so that they can be easily found... What happens is a hard disk dies?