At the end of tape from Radiohead's OK Computer OKNOTOK 1997-2017 bonus material there is a ZX Spectrum program. Also, inside the code there's a hidden, black text on a black background: "congratulations....you've found the secret message      syd lives       hmmmm. We should get out more". If you would like to repeat this yourself here is a guide how to do this written by Maciej Korsan: https://medium.com/@maciejkorsan/how-to-run-secret-zx-spectrum-message-from-radioheads-oknotok-c90-tape-795bfd429ba1

Note that you need to filter the audio with 3.5kHz low pass filter.

Thanks to Maciej Korsan for the audio recording :-)

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