The concept behind RAID (redundant array of independent/inexpensive disks) is that a level one RAID will provide disk mirroring. A technique in which data is written to two duplicate disks simultaneously. This way if one of the disk drives fails, the system can instantly switch to the other disk without any loss of data or service. Disk mirroring is used commonly in on-line database systems where it's critical that the data be accessible at all times, but isn't generally necessary for personal computers.
While hard disks are cheap enough for building a RAID setup, what you will end up with is a bunch of hard disks sitting somewhere with all of your pictures on them. They will fail at sometime, you just cannot tell when.
/DVD technology has progressed sufficiently to the point where they have become extremely reliable and inexpensive. I have found that making two back up copies of the days shoot on CD
, and then when I have enough to fill a DVD, I then copy individual days onto a DVD. I usually make two copies of that as well. Keep them in different locations for safety and you should be fine.
When making prints and storing in an album, I usually burn a CD
of the albums images and stick it in a sleeve inside the album. That way years down the road, an original image file will be handy, as it is on the CD
inside the album. Much better then negatives.
What you may want to do is visit some of the digital photography forums and read up on different organization methods. Ken is right. You are going to have so many more images then with film, and you will need an orderly method to catalog them, regardless of how you store them.