There seem to be plenty of utilities available for this kind of housekeeping on MAC systems on which iTunes is a native application. But it took a little digging to find these helpful little utilities. There are about 20 utilities of which I see a use for about 3 of them for my purposes.
Every once in a while I like to re-evaluate some of my playlists and/or create new ones. I don’t necessarily want to throw away my previous work (although sometimes I do that too…), so I wanted to be able to toss songs into, say, my “Driving” playlist without concern for whether or not those songs were already represented there.
Running Teridon’s script allows me to simply purge all the duplicates after I’m done. A handy little time saver.