Haven't used amanda, have you? Just set yourself up with a decent-sized holding disk and it's not a problem. (Your backups will finish fast, too.) My amanda server at work can easily run a week's worth of backups without needing a tape, just saving it all up on the holding disk. Just be sure the holding disk is a separate physical device to minimize the chance of losing it if the system's primary drive fails.
I would like to use CDR instead of tape, but I've heard that Amanda requires you to use a new tape for each session (good or bad). If I wait until the end of the week, assuming I've accumulated only 500-600MB of changes, will it back it all up onto the single CDR? What if it accumulated more than would fit on a disk, would it span multiple disks?
Also, if you wait until the end of the week, does Amanda keep multiple generations of the files modified during that week in the holding disk, or only the most recent modification?
-- Bobman