1. Backupninja

... incremental data, backup system and hardware info, encrypted remote backups (via duplicity), safe backup of MySQL/PostgreSQL databases, subversion or trac repositories, burn CD/DVDs or create ISOs, incremental ...

2. Duplicity

Duplicity backs directories by producing encrypted tar-format volumes and uploading them to a remote or local file server. Because duplicity uses librsync, the incremental archives are space efficient ...

3. Backup to Amazon S3 using Duplicity

... remote backups with it, and its package is existing in the Debian package repository. I looked into/around several open source backup applications: Bacula Zmanda rsync rdiff-backup duplicity ...