Proposed Solution:
I've really grown to appreciate the new References window that was recently added to CodeRush. One thing that I think would be helpful would be to have an option on its toolbar for including line numbers for each reference found. The options that are there now for showing parent member, class, project, file, and so on are nice... but unless the References window is made very large, it's sometimes hard to get a sense for where in the file the Code Preview actually is. I know I can double click one of the found references to make the editor jump there, but having the line numbers would be useful.
I could see adding the line numbers to the Code Preview (provided it used the same formatting/color as was defined for the VS.NET editor)... but it would also be fine just to have it appear as a small item next to each reference listed in the results.