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.
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Display, create text file listing info of dead tracks
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Locates pairs of track entries pointing to the same file
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Fill a playlist with user-set number of randomly selected full albums
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Apply selected CD's CD Text to its disc and track tags