We are today open sourcing a simple tool called Automated EBS Snapshots for managing AWS EC2 EBS snapshotting. It makes it possible to monitor an EBS volume and create snapshots every hour, week, month or year.
To start making daily backups of a certain volume, run the command below (but with your volume ID of course)
automated-ebs-snapshots --config ~/auto-ebs-snapshots.conf --watch vol-12345678 --interval daily --retention 7
--retention flag instructs Automated EBS Snapshots to keep 7 snapshots. All older snapshots will be deleted.