I setup a backup system for a lawyer last year. Its basically a cron job that runs a script every night. It uses duplicity + gpg and stores everything on amazon s3. Its incredibly cheap. I store 6 months of revisions, with a full backup on the first weekend of every month, then incrementals after that. I perform regular restores and run a big md5sum job to ensure that the restores are working. I havent automated that stage of it yet, but so far so good. I'd be happy to send you the scripts if you want. PM me if youre interested.