But it turns out those pieces of text weren't just random writings from the band -- they were actual lyrics from their next two albums, 2001's Amnesiac and 2003's Hail to the Thief. Yep, the satanic-looking secret booklet printed the lyrics for songs that wouldn't come out for three years. Granted, it's pretty common for bands to leave songs off of albums and re-use them later, but it's still very cool that those who found the booklet got a preview of the future.

Thom Yorke's bed-sheets and walls are covered in "previews" like this.

And what do you know, after Hail to the Thief, Radiohead was finally free of their recording contract and went independent for their next album, 2007's In Rainbows. And speaking of In Rainbows ...

There's a way to combine the tracks from OK Computer (hereinafter referred to as 01) and In Rainbows (hereinafter referred to as 10), to form one huge mega-album. As Puddlegum explains, "To create the 01 and 10 playlist, begin with OK Computer's track one, "Airbag," and follow this with In Rainbow's track one, "15 Step." Alternate the albums, track by track, until you reach "Karma Police" on OK Computer, making "All I Need" the tenth track on the 01 and 10 playlist." It's not that they sound nice together; it's that these songs were definitely meant to make us shit our pants when played like this. In the way that "Golden Slumbers," "Carry That Weight" and "The End" all flow into each other on The Beatles' Abbey Road, these songs all flow into one another as well, as if they were all recorded in one big session.

Don't believe us? Just listen to it. To get the full effect, you need to set your player with a 10-second crossfade between tracks (more 10s!), but you can notice most stuff without doing that. Then shit your pants.

Is Thom York moody, or is he acting like he just crapped his pants
as a really subtle clue?

This blogger points out that the song "Nude" (10 album), starts with the reverb from "Subterranean Homesick Alien" (01 album) still lingering, and the beats at the end of "Airbag" (01) set the tempo for "15 Step" (10). There's nothing unusual about that ... except when you consider that those songs were written and recorded 10 years apart. The pants-shitting synchronicity also applies to the lyrics. Puddlegum gives some examples and says: "There appears to be a concept flowing through the 01 and 10 playlist. Ideas in one song [are] picked up by the next." In fact, one of the songs from In Rainbows was originally written for OK Computer and not used for 10 years, and the title of another seems to sum up the whole thing: "Jigsaw Falling Into Place."

Alternate way to sum it up.

Remember all that "10" stuff we mentioned up top, about the date, the time between albums, the number of letters in the titles and whatnot? Want more? Radiohead themselves announced In Rainbows only 10 days before it came out (which is rather unusual), and the announcement was followed by a series of 10 cryptic messages posted by the band on their website. That's nothing new: Cryptic messages might be the only way alternative rock musicians know how to communicate. But then Radiohead fans, being Radiohead fans, noticed that the messages emphasized the letter X (one image was titled "Xendless Xurbia"). And, say, isn't "X" the Roman numeral for 10? Plus, let's take a look at this cover art real quick.

Oh, look, two 10s. Huh.

The band has never officially confirmed any of this, though Puddlegum claims Thom Yorke was annoyed by how long it's taken people to figure it out. Come on, dude -- not all of us are insane alien geniuses.

Well, the difference is that, in this case, you don't get the full song by doing something as mundane as playing one track after the other -- you get it by changing the order and playing them at the same time.

By themselves, the songs seem completely different: "10,000 Days" (11:13) is a long prog-rock number, "Wings for Marie" (6:11) is a quiet song that builds up into a crescendo, and "Viginti Tres" (5:02) is just a bunch of weird noises. 6:11 plus 5:02 adds up to 11:13 -- that's because you're supposed to put "Viginti Tres" and "Wings for Marie" together (in that order) and play them at the same time as "10,000 Days."

Sobriety is optional, but not recommended.

If that sounds too complicated for you, check out this demonstration at YouTube-Doubler. You'll notice that the weird sounds from "Viginti Tres" seem to be in sync with the melody of "10,000 Days." That demonstration doesn't include "Wings for Marie", though, which has the most impressive part: Near the end, the vocals from both songs alternate almost perfectly, forming completely different lyrics.

The band has never acknowledged any of this, but if you listen to the full song it's pretty obvious that they did this intentionally ... which is both mind-blowingly awesome and a little bit insane.

Also like Voltron.

Calling Richard D. James (the founder and sole member of alternative rock band Aphex Twin) an eccentric is hardly a stretch. He lives in a converted bank office owns a tank and submarine, and has a deranged compulsion to plaster his face all over shit, as seen most prominently in the insanely terrifying music video for "Come to Daddy."

Things like this should not happen in music videos. Or anywhere.

But, apparently, exposing your eyes to images of abject horror isn't good enough for Richard D. James. He wants you to hear those images, too. His 1999 single, "Windowlicker," included a B-side with the catchy name of ...

... (fans just call it "[Equation]," unless they're real douchebags). Five minutes and 30 seconds into the song, a metallic, buzzing noise is heard, which is frankly nothing out of the ordinary for Aphex Twin. What IS fucked up is that when you run that section through a spectrograph (a program that converts sound waves into visible images), this comes out:

You weren't planning on sleeping tonight, right?

The insane, nightmarish grin of Richard D. James himself is entering your ears in the form of sound waves. You can see the image being formed bit by terrifying bit here, if you must. Encoding photographs into sound is actually pretty simple (you just need to find the right software), but not everyone can get away with taking the resulting mess and slapping it into a song.

Richards isn't the only one who has done it, though. Nine Inch Nails hid part of their album's cover art in two songs from the album Year Zero, and lesser-known electronic artist Venetian Snares included spectrographic pictures of his cats ... in an album titled Songs About My Cats.

OK, now we can't decide which one is scarier.

"Hello, hunters. Congratulations. You have just discovered the secret message. Please send your answer to Old Pink, care of the Funny Farm, Chalfont--"

... and then the speaker is interrupted by a female voice saying someone is on the phone. Not exactly "DELIVER YOUR ANUS UNTO SATAN." We're afraid that's about as exciting as real instances of backmasking get -- unless you count grunge band Ash hiding an entire song on their debut album, Trailer. When reversed, pitch-shifted and sped up, the noise at the end of Track 5 actually turns out to be a demo track of another song on the album. What's so neat about that? The album was released in 1994, when the cost of the audio equipment and/or software to hear the song would have put it out of the reach of the vast majority of listeners. That's several layers of hidden. This would all be a whole lot more impressive if anyone actually knew or cared who Ash was.

These guys look more like the roadies than the band.

That's probably (definitely) what happened to anyone who listened to Monty Python's Matching Tie & Handkerchief album (which, to add to your mental stress, did not always come with a tie or a handkerchief). One side of the album had two completely different sets of tracks, and you never knew which one you'd get until you played it. How was this possible? Well, for starters, you need to have the original vinyl version of the album, which requires being over 40 and/or a weirdo.

Lots of vinyl albums used lock grooves. That's when the needle reaches the end of the album and instead of, you know, ending, it keeps playing the last part in a loop. The Beatles did it with Sgt. Pepper's, which ended with a "sound designed to annoy your dog" and an endless loop of laughter and gibberish.

In case you were wondering why they'd do that.

But then there are double grooves, which is when the album's grooves are pressed in a way that makes it so you get a completely different set of tracks depending on where the needle lands. That's what Monty Python did, and the best part is that they didn't bother to tell anyone about it, creating real confusion in the audience. Also, the record sleeve didn't even list the album's tracks, presumably so that there was no fucking way you could prove to your friends that you weren't lying about what you heard. On top of that, both sides were labeled "Side 2," making things even more maddening.

We're fairly certain Graham Chapman was an Elder God.

Mr. Bungle later did something similar in Disco Volante: If you play the record from the beginning, you get the normal tracks, but if you drop the needle at a specific point in the middle, you can hear a secret song (as long as you have the U.S. vinyl version). But then again, chances are anyone listening to Mr. Bungle is already on drugs and won't think much of that.

On first look, the artwork to Led Zeppelin's In Through the Out Door is the most boring in their whole discography -- the front cover is just a photo of some guy sitting in a bar, and the inner sleeve shows crude black and white drawings of the contents of the table. Where are the naked aliens crawling through rocks? Where are the exploding zeppelins, bizarre obelisks and satanic references?

Why have they stopped trying to make us feel uncomfortable?!

But the album art is only boring on the surface ... literally. If you wash the inner sleeve with water, those lame black and white drawings become permanently colored. And since no one intentionally gets water on their albums, this means most people probably found out about this when his asshole roommate spilled bong water on it.

"Hey, what the fuck are you ... Whoa."

The artwork uses the same special watercolors employed by some coloring books, but the band never advertised or even mentioned this feature, so you could have owned the album for decades without realizing you could do this (as a simple eBay search reveals). And even then, most painted sleeves we could find are only partially colored, like the one above, probably because so many people had heart attacks shortly after discovering this.

You probably know about hidden songs at the end of a CD, typically after a long silence or multiple blank tracks. Some, like "Endless, Nameless" from Nirvana's Nevermind, are famous in their own right. On the final track of One for the Kids, Yellowcard has a hidden song that shows up only after a silence that lasts for exactly 4:20, because they're very subtle.

It isn't easy to find photos of Yellowcard concerts that aren't obscured by billowing clouds of blunt smoke.

Most are just good for scaring the shit out of you when you forget you left your CD player on and are starting to fall asleep. There are other ways to hide a song, though, like before the CD even starts.

Before the first track on any CD, there's a section of data called the pregap, which is typically used to store structuring data for the disc itself. But a few enterprising artists found a way to place audio in the pregap, which is like putting the salami on top of the bread. To access the pregap, you must go against your every instinct by pressing and holding the rewind button at the beginning of the first track, until it can't go back any further. This will often show a "-1" in the display window, with all the creepy associations that brings to Super Mario Bros. players.

Aaaaaahhh!

Lots of bands have hidden stuff in the pregap, and they're not always limited to the first track, either. Progressive rock band Dream Theater hid instrumental intros on half the songs on their album Octavarium. Most pregap tracks are stuff like that -- short intros or band chatter -- but then there are bands who try to get more creative with it, like Public Enemy did in their 1994 album Muse Sick-n-Hour Mess Age.

Public Enemy is usually associated with old-school hip-hop, but in this album, Chuck D recorded and hid a full freestyle rap titled "Ferocious Soul," with lyrics mocking the critics who had accused the band of being "anti-black" for saying that gangster rap had negative messages, since it promotes unrealistic things like ridiculous wealth, being constantly surrounded by titties and owning insane amounts of jewelry (shaped like titties). Old-school hip-hop's lyrics were considered silly in comparison by rap fans.

Pictured: A far less silly representation of life in urban America.

And all you have to do to listen to this rare gem is press rewind. Simple, right? Well, it would be, if it wasn't for the fact that most pregap songs aren't accessible anymore. Nowadays, electronics manufacturers have to build their products to a standard known as Red Book audio, and pregap audio goes against those standards. As a result, the majority of stand-alone CD players and computer optical disc drives can't read pregap audio. ITunes and other media players won't recognize it and the tracks are typically not available for sale from online music retailers. On the upside, this means those tracks the artists meant to hide are really well-hidden now.

If this is as urgent as they say, you sort of question the logic of why they'd hide it in such an impossible-to-retrieve format. Most listeners at the time had no idea something like this was possible (shit, we live in 2010 and we didn't either), so even if they were computer-savvy enough to understand the title of the song, they probably thought it was an obscure joke.

"How do we make sure that only huge, huge nerds listen to our music?"

Before Information Society, other bands had used a similar method to encode stuff like lyric sheets, promotional information about the band and even a full adventure videogame in all its pixelated glory (you can play in your browser by clicking here). In those cases, you had to record the songs into an ordinary audio tape and then play the tape in a Sinclair ZX Spectrum computer to watch the results (provided your mom didn't yell at you while you were recording the audio, because then you were fucked). None of these were actually hidden, since they were all intentional and advertised features, but they're still pretty awesome.

Artists from decades ago were so much more productive. All we get out of Kanye are a bunch of retarded tweets.

And this.

To read more of Ashe's work, check out weirdshitblog.com.

Maxwell Yezpitelok lives in Chile, and when he isn't waiting for the next catastrophe, he likes to waste his time writing back to scammers or making stupid comics.

For more creepiness discovered in music, check out 6 Musicians Who Predicted Their Own Death in Song. Or learn about some artists with skeletons they hope you forget about, in 7 Beloved Celebrities And The Awful Shit You Forgot They Did.

And stop by Linkstorm to discover the hidden messages we leave in all our articles. (They're mostly dick-based.)

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