S3 Interfaces for Backup, etc [closed]
I'm really happy with Jungledisk which provides a WebDAV interface to S3. You can simply use it for mounting filesystems, or use the included backup features (which uses rsync for incremental backups). Great support too :)
The S3 support in duplicity worked fairly well for a company I was working for. It didn't "mount" the filesystem as such, but it did do nicely encrypted backups.