Set the Plays ("Play Count" before iTunes v9.2) of the selected tracks to a user-entered number (they will all be set to the same number). If this number is 0 then the Last Played date of each track will be erased. (iTunes has the ability to "Reset Plays" to 0 from a track's contextual menu.)
Also see Add or Subtract Play Count.
Apple Music users should beware of a potential bug.
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Removes leading and trailing space characters from chosen tags in selected tracks
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Search Wikipedia using the Song Name, Album, Artist, or Composer of selected or playing track
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Sort purchased tracks into discrete playlists by name or Apple ID
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Applet assists with swapping, copying, appending data between track tags