Hidden tracks on albums are, to use an obvious metaphor, like buried treasure: When a tune you're not expecting suddenly starts playing, it's several steps higher on the excitement meter than finding the prize in a Cracker Jack box. In today's singles-centric digital era, hidden tracks aren't quite as fun -- and they're rarely even unexpected -- but back in the day, before iTunes, Rhapsody and Spotify replaced CDs, cassettes and vinyl records, they were quite a big deal.

There are several reasons artists put secret tracks on albums. They're useful for creating mystique around songs; for adding humorous effect, in the case of joke tracks; and for sneaking on tunes that, for whatever reason, are considered controversial. The list of standout hidden tracks is seemingly endless, but we here at Diffuser.fm focused on five for this feature, which we cooked up with our friends at Loudwire and Ultimate Classic Rock. Click the button below -- bright blue, not at all hidden -- to see our picks.

  • 'All By Myself'

    Green Day

    Green Day's multi-platinum breakthrough disc, 'Dookie,' ends with a quirky, 80-second acoustic ditty that features frontman Billie Joe Armstrong singing lyrics penned by drummer Tre Cool about being "All by myself" -- and nearly breaking down into hysterical fits of laughter in the process, possibly due to being really stoned. Not surprisingly, the lo-fi 'All By Myself' was left off the official 'Dookie' track listing, but it remains a favorite among Green Day's biggest fans.

  • '11'


    The hidden final track on R.E.M.'s 1988 major-label debut, 'Green,' sure goes by a lot of different names. Unlisted on the back sleeve, the song is copyrighted under the title '11,' but it goes by simply 'Untitled' in the iTunes Store and is often referred to by fans as 'The Eleventh Untitled Song.' "At the time it was really cool to have unlisted, 'hidden' tracks for the fans, and that was ours," singer Michael Stipe once told the Pop Songs fansite. "It's untitled because we just pretended like it didn't exist."

  • 'I'm Going Crazy'

    Smashing Pumpkins

    The gorgeous string-laden acoustic ballad 'Daydream,' sung by then-bassist D'arcy Wretzky, seems to close out the Smashing Pumpkins' 1991 debut, 'Gish,' but it's actually a 30-second ditty titled 'I'm Going Crazy' that ends the album. The unlisted surprise launches about 10 seconds after the conclusion of 'Daydream' and basically amounts to frontman Billy Corgan singing about a descent into madness, repeating the line "I'm going crazy" several times over tambourine and fuzzy guitar.

  • 'Classy Plastic Lumber'

    Modest Mouse

    "BA BA BA BA BA," Modest Mouse frontman Isaac Brock sings out several times at the start of 'Classy Plastic Lumber,' an infectiously poppy hidden gem on the 'Float On' hitmakers' 2001 album 'Sad Sappy Sucker.' Unlike many hidden tracks, 'Lumber' isn't featured at the end of the album. Instead, it's the fourth track, and because it wasn't listed on the original back sleeve, all of the songs after it are out of order.

  • 'Life Is for Living'


    Coldplay's 2000 debut album, 'Parachutes,' was an undeniable hit on both sides of the pond, but it only hinted at the massive international success that was in the British quartet's future. The hidden track 'Life Is for Living,' however, perfectly encapsulates a major theme of all the band's subsequent albums: Live life to the fullest -- and find somebody to join you along the way, if possible. Who can argue with advice like that?

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