If you're a professional and your images are a business asset, then it's obviously a more important thing than losing something you created just for fun. Which is to say I'd be very careful with what I shoot for fun (which is all of it for me) but even more cautious if I were doing hired work.

I rarely print and rarely save a converted RAW file, because I usually don't do much to them anyway. On my Mac, I use a program called "Super Duper" (I know, stupid name but great program) and just back up the whole system. Some recent image files will stay on this computer but the majority go to another hard drive.

Some of the ones I really like get the expense of that $1.75 DVD as another backup.