OS X 10.8 or later. Set Last Played/Last Skipped date of selected tracks to a new date, with option to increase or decrease Plays/Skips, or set to no date and no Plays/Skips.
Also see Add or Subtract Play Count.
Like so. The Last Played date of the selected tracks will be set to June 10, 2014 at 9:45AM and the Plays will be decreased by 3. The latter is an option that can be toggled on and off with the checkbox.
Edit a selection of iTunes tracks' tags "old-school"
Re-associate batch of dead tracks with files from selected folder
Re-locate files of selected tracks to new folder, preserve track meta-data
Select iPod tracks in iTunes and add them to iTunes
Set choice of various number tags of selected tracks incrementally
Display, create text file listing info of dead tracks