The "Search Filesystems" result window has a problem revealed by a recent usability test.
Participants, either didn't see the list of positions on the right (often because it was obscured). Even when they did, they didn't realize they 
could double click on an individual position.  Instead, all participants double-clicked on the file names  in the left panel and then tried to 
locate the relevant text within the source window by hand, with the Find command or by looking up the line number listed  in the Position 
list.

It might be good to intermix the information on the left and right panels in some manner.  For instance, if a tree were used, expanind a file 
might show the positions within it (the relevant line of text could be shown to the right of this as well).  Such as

* My File
  -  34:   sample source line
  - 123:  another sample line
* My Second File
  - ...