Is there a service out there to auto backup our S3 account to a external cloud?
I can't think of anything off the top of my head, but it's really trivially simple to do with the S3 API, and another cloud's API. You'd probably need an intermediate server, unless the 3rd party has a HTTP Pull method.
I'd probably set up an EC2 micro instance running ubuntu, or something, and script a cronjob that copies new files to the other cloud. You could use
I'd probably do it in python with python-boto. Seems to work quite well for that kind of S3 manipulation.
If your cloud provider has a HTTP Pull method, then you could just set the ACL on the S3 objects to allow authenticated HTTP access, and copy them over that way.