CD Session Burner can burn multiple sessions to the same disk until all the space is used up. This makes it terrific for making incremental backups. When you use a multi-session CD each session is mounted as a separate volume.
Would really like this app to work but i have tried it 2x and each time it reports an error (doesn't say what) and the barber pole seems to hang. I emailed the author and have received no reply since 2 weeks ago. I've got to back up so I'm looking for other options.