Stardock has released KeepSafe 1.1.  KeepSafe is a program that will automatically archive files on your computer of a specified file whenever they are saved.  Users simply pick which types of files (.doc, .jpg, etc.) they want to keep safe, then choose a location for their archives to go, and presto. From then on, KeepSafe silently keeps your data safe. When it creates an archive, it saves previous versions as revisions. As a result, users can go back to a particular version of a file. If you've ever had a file become corrupt or accidentally deleted a file or had someone make changes to it (like a network shared file) then KeepSafe is definitely for you as it would be able to recover previous versions.

KeepSafe 1.1 adds "Diff" support so that only changes in new versions are saved rather than the entire file.  You can try it out for yourself.  Stardock originally developed this to solve the problem of people simply not making backups. The solution, KeepSafe, integrates data archiving into the file system itself. 

Download: KeepSafe 1.1

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