If you're someone who inks traditional drawings before coloring them, like me, scan them when you're finished them, in as high quality as you can. If you don't have a scanner, a good camera will do.
Why am I saying this?
Well, I had done about 5+ hours penciling and inking one of my commissions, with an hour or two of research in anatomy behind it, only to somehow lose it, which is extremely rare for me. Thankfully, I have a habit of scanning all of my inked works before coloring them, and scanning them when they're finished. I usually have the scans saved on my computer and on my USB stick. So I was able to find it on my USB (hadn't put it on my computer for some reason), put it into an OpenOffice document and print it out, looked almost as good as the original. So relieved.
I try to scan/take pictures of all of my artwork, so that I can put it on my iPod and show them to people who are interested in my art, and as backups. And, of course, to post on dA and other sites! Scanning can save you a lot of stress if you happen to lose a drawing.