So, I still need to release my backup module for Drupal 5. But I haven't had a chance to sit down and actually read the documentation.
But, awhile back, I developed my own command-line utility for backing up my own Drupal websites. Since it was quicker to clean that up and release it instead of waiting for me to Finish the Drupal 5 version of the module, I figured I would do that.
It needs to be run from the root directory of DOCUMENT_ROOT from the command line. It will automatically read in your default settings.php file to get the database credentials and create its own backup of the database. Then it will backup the webserver's filesystem and store both database backup and filesystem into a nice little tarball, ready for download via your web browser.
For those of you who are worried because the file is essentially world-readable, there is a random number appended to the database dump and the final backup to prevent an attacker from guessing the name of the file. (your webserver would fall over from the 404s before someone successfully guessed a filename)