Backup Box helps you connect technologies that don't play nice together, like FTP and Dropbox. Free, automatic, and behind the scenes. No installation required.

Unison is a file-synchronization tool for Unix and Windows. It allows two replicas of a collection of files and directories to be stored on different hosts (or different disks on the same host), modified separately, and then brought up to date by propagat

Jungle Disk is an application that lets you store files and backup data securely to Amazon.com's S3™ Storage Service.

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