The past decade has been a boon for music lovers (once you get past the whole most-digital-music-sucks thing). The iPod turns 10 years old this October; as you’ll no doubt recall from much of the commentary at the time, it was Apple’s biggest mistake and quickly vanished into obscurity.

But the iPod wasn’t the world’s first portable digital music player… and it wasn’t even Apple’s first foray into that space. That honour goes to iTunes, which turns 10 years old on Sunday.

iTunes has turned us all into our own personal DJs, with the ability to create and update playlists – either manually or automatically, using iTunes’ powerful Smart Playlist feature. You end up with separate playlists for the gym, for your morning commute, for your afternoon commute, for dinner parties, for keeping the kids happy during long drives, for getting the kids to fall asleep during long drives…

But one of the side effects of playlists is you start to forget the stuff that isn’t in them. Apple gives you a Smart Playlist called “My Top Rated”, but that can quickly become a self-fulfilling (and repetitive) prophecy if you aren’t diligent about rating your songs. You may find that you have thousands of songs on your iPod, iPhone or Mac, but you end up listening to the same handful over and over again because, well, they’re the ones that are in your playlists.

Now, if you’re the kind of person who relentlessly mines their music collection to freshen their playlists, then you don’t have this problem. But for a lot of us who don’t do that kind of spelunking very often, and who have songs that we’ve actually forgotten we own, a little automation can help unearth some lost gems.

So I’ve created two Smart Playlists to help me keep the hits coming.

The first is for routine listening. It uses several criteria:

• Rating is greater than three stars.
• Genre is not Podcast, Children, Voice Memo, Comedy or Spoken Word
• Media Kind is Music

I limit the list to 100 songs, selected by least recently played.

The result is a playlist include songs I’ve liked in the past, but haven’t heard recently. (Depending on your listening behaviour, you’ll want to tweak the rating setting to populate the playlist with enough songs. You may also need to exclude a few more genres.)

The second is for discovery. I duplicated the first playlist, but changed the rating criteria to less than one star – that is, unrated. As I listen to that list, I find I do a lot of skipping… but I also rate the songs as I go. (And often I’ll just plow through a bunch of them in iTunes.) That helps to feed my routine listening list as well as all my other Smart Playlists that rely on ratings.

Thanks to this setup, right now I’m listening to “Somehow” by The Vapors, which I haven’t heard in years. Next up is “The Way It Goes” (iTunes) by Wild Strawberries. If you try something like this, and recover some long-lost treasure from the dusty corners of the iTunes vault, let me know what it is.

Update: Kate Trgovac has created what I now consider to be the good version of this post, including the key missing ingredient: a screen shot. And if you want to take a more rigorous (and quite possibly more satisfying) approach, check out this amazing system of playlists and scripts from Maximilian.