This is pretty crazy!
While many reissued albums include special treats and hidden surprises, I think this one from Radiohead takes the cake!
The band reissued their album "OK Computer" for it's 20th anniversary, and left something for fans to geek out over...if they can figure it out.
Turns out there's a hidden computer program along with the re-release!
The deluxe box set edition of OKNOTOK contains what is described on Radiohead’s web store as a “C90 cassette mix tape compiled by the band, taken from OK Computer session archives and demo tapes.” Users on Reddit’s Radiohead board realized that the sound that opens the tape is the startup music from the ZX Spectrum, an ’80s 8-Bit computer from the UK that was used to create some sound effects on OK Computer’s “Let Down.”
From there, a Redditor realized that the end of the cassette contains an audio message designed to be fed into the Spectrum, which ran programs from cassette tapes. After some tinkering, another Redditor named Maciej Korsan got it working on a Spectrum emulator and uploaded the results to YouTube.
Wow! That's some heavy detective work! Check out what the computer program looks like: