I\'m pretty happy with s3cmd, but there is one issue: How to copy all files from one S3 bucket to another? Is it even possible?
EDIT: I\'ve found a way to copy files
AWS CLI seems to do the job perfectly, and has the bonus of being an officially supported tool.
aws s3 sync s3://mybucket s3://backup-mybucket
http://docs.aws.amazon.com/cli/latest/reference/s3/sync.html