FileGhost
Snapfiles has a review of a program that could be very useful for some.
FileGhost enables you to restrict access to your files and folders, and even entire drives. You can choose from different protection methods and either block access to selected folders or files, or define specific limitations that prevent users from changing or deleting the protected files. The program includes options to securely lock, hide, deny file reading, deny file writing, prevent deleting, copying, moving, renaming and replacing, and prevent file attributes or file timestamp changes. The interface is easy and straightforward to use, just select (or drag and drop) the files/folders and set the restrictions using checkboxes. The interface can be password protected to prevent tempering with your settings.
Check out the trial version from Snapfiles here