backup an 80GB hard drive to multiple DVDs?

hey all,

My MacBook looks like it will need repair, and sooner rather than later. I made an appt at the Genius Bar this evening (Fifth Avenue, NYC store) and I need to backup my data. I have a DVD burner and plenty of DVDs, but I don't have Toast and can't purchase Toast or anything else right now.

Is there a free way to make a backup disk image of my drive over several DVDs? Or do I have to copy one folder at a time until each DVD is full and then just copy everything back individually if a fresh install is necessary?

sps