Aside from backwards messages (which is a seperate page), bands have found other interesting ways to hide things in their music or in their album covers.
Entries Beginning with M
The beginning of the song when played backwards contains lyrics that can be understood as referring to snakes, homosexuality, witchcraft and the line 'they all stare'.
tictacs941
At the start of the 2nd verse, you can hear a faint "Hey" after Serj says "Hey, Mr. Jack".
Glenn Rousseau
At about 2:46 (about 2/3 into the song) part of an older track by the same band (called Jesus Freak) breaks into the song, followed by what I'm sure is lyrics from the Gotee Brothers hip-hop version of the same song.
Bryan Pardue
"My Sweet Lord," George Harrison / Beatles
Toward the end of the song the background vocalists switch from singing, 'Hallelujah' to 'Hari Krishna', reflecting George Harrison's religious interests at the time.
cavrev
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