Based on this great blog post by Tim McCormack, I managed to write some scripts that back up files to Amazon S3. The files are encrypted with GnuPG and rsync-ed to S3 using a Python-based tool called duplicity.
"Independent developer Mark Atwood has been working on a MySQL interface to Amazon S3. Released under the GNU Public License, the code is compatible with version 5.1 of MySQL."
With the new version of OS X (Leopard) Apple has included some great functionality in Time Machine. Your Mac will automatically backup to an external drive every hour. It includes the ability to recover deleted files in a timeline.
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