I thought I'd post the little script that I use to run daily backups of my WebGUI databases. It's quite short, so I'll just paste it in-line here.
I put an entry into my crontab that looks like this:
39 5 * * * /data/WebGUI/baks/bkup_wg_dbs >>/data/WebGUI/baks/bkup_log
This runs the backup script (bkup_wg_dbs) at 05:39 every morning and appends the results to the file 'bkup_log'.
You could change the directory naming scheme (using different formatting options on the date command) to accomodate different kinds of backup strategies. I happen to prefer this "date.time" format.
One of the useful things I included is that the script also creates a 'restore' script that can be run from the backup directory to restore the entire database, making it very easy to go back to a prior database instance.
-David