Strongsync provides Dropbox-like sync and backup using only SFTP or Amazon S3. Strongsync lets you connect to your own SFTP server or Amazon S3 account so you stay in complete control of your data. SSH (SFTP), Amazon S3 and Dreamhost DreamObjects support. Rackspace Cloud Files, Openstack Swift and other backends coming soon. SSH keys support. Encrypted connections via SSH and SSL. Deduplicated content-addressable data storage. Strongsync sports a clean and simple user interface designed to stay out of the way.