Multiple archives on one tape

[Bill Lasher]

We have an environment with a large number of users (~400) on a group of
machines.  I am looking for a simple way for these people to archive files.
We have 1/4" cartridge tapes, and tar (or bru) won't allow you to append
archives.  The result is the users have lots of tapes with small files on them.
Any suggestions that won't require the users (they are students) to buy *REAL*
expensive tapes?

Bill

P.S. Floppy drives won't do it; some of the files are too large (up to 20M).