A new feature of Duplicate File Detective v3.0 that's receiving a lot of praise is its ability to replace duplicate files with shell shortcuts.
This is a very powerful concept, allowing for removal of duplicate files while still allowing end users to access to the original copy through the previous file location. This feature is implemented in Duplicate File Detective as part of the Duplicate Result Manager dialog window:

As you can see in the screen shot above, there is an option to replace moved or deleted duplicates with shell shortcuts to their unmarked siblings. The option becomes available anytime you execute an operation that results in the movement or deletion of duplicate files.
So how exactly does duplicate file shortcut linking work? The key is to remember that Duplicate File Detective organizes duplicate files into groups. In the screen shot below, you can see that each duplicate file group has an alternating background color, as well as unique group number (as shown below the Group column header). Also note that, in the example below, we've marked all but the first duplicate file in each group.

When replacing duplicate files with shell shortcuts, the first unmarked duplicate in each group becomes the link target for all other files in the same group. In other words, in the example screen above, the first (unmarked) "tulips.jpg" file would become the shell shortcut target for all the remaining (marked) "tulip.jpg" files. If there are multiple unmarked duplicates in a group, then the first of these will be used as the shell shortcut target.
Once the Duplicate Result Manager completes file processing with the shell shortcut option engaged, the marked duplicate files of each group will be replaced by shell shortcuts to the first unmarked duplicate in the same group.