Here’s a pretty good instruction at Dropbox.  I didn’t follow the instruction exactly, but I’ve repeated the step enough times to know that it works for the most part.  I had some problems with my Python 2.6 installation after incrementally upgrading from 8.04 -> 8.10 -> 9.04 -> 9.10, but it’s all good now.  Anyway, on my VPS host, I set up several cron jobs to dump mysql databases and svn repos, rsync contents of some /var/www and tar-gzip contents of /etc, /root, and /var/log.  I don’t need to keep multiple versions of the backups because dropbox automatically takes care of incremental backup and versioning.  One thing to be aware, however, is that Dropbox doesn’t encrypt data, either in the transmission or storage, so you might want throw something like TrueCrypt or GnuPG in the mix.

Once backups are set-up with Dropbox, you can even subscribe to the backup/revision history RSS feed(s) provided by Dropbox to stay on top of the status.

Several other useful resources:

• Encrypting Your Dropbox Seamlessly and Automatically
• Dropbox With Personal Encryption