For many years now I've had a pretty inexpensive system of file back-up in place. All of my files live on my computer's hard drive (copy #1). Any project in process is backed up onto an external drive every day when I'm finished working (copy #2). Once projects are completed they are set aside to be archived. When work is slow, like now, I burn files ready for archive onto CDs or DVDs. I make one set that is kept here in my office (copy #3) and another that is sent to live on a shelf at my husband's office at work (copy #4). Should the worst case ever happen and my house burns down, I would have a copy of all my files safe and sound.
A little van Gogh livens up the cover and a burn date helps me find files later. Inside is a listing of the contents of the disk to further help in finding that certain file years later.
