I'd be very wary of anything from Dantz, their Retrospect software used to be the king of backup software back in the OS9 days, then they got bought out by another company and the quality of their software has been lacking ever since. You need to be able to *trust* your backup!

I highly recommend that you consider ChronoSync software for OSX backups. It's what I use with an external 200 GB hard drive.

Another tip: upgrade to OSX 10.4, and transfer your entourage database to Apple Mail app. After using MS outlook express/entourage for many years, suffered through a nasty crash of their buggy database limitations (you know that beyond a 2GB database size, you're liable to crash, and crash hard), I am much happier with Apple Mail, and the latest version that comes with Tiger satisfies all my emailing needs, along with a better spam filter capability! Plus it stores email in a standard text format, not a proprietary humungous database file format, an extra safety net should the inevitable happen.