As far as music trivia goes, we all know about 'Forever 27' which is the strange but true fact that musicians historically have had a bad pattern of passing away too early at the young age of 27 (Jim Morrison, Janis Joplin, Jimi Hendrix, Kurt Cobain, Amy Winehouse, Robert Johnson, Mia Zapata, and Brian Jones to name a few). We all know that "Stairway to Heaven" attempts to speak to Satan when played backward. We all know that Eric Clapton wrote a few tunes in reference to George Harrison's wife. The song "Layla" is a perfect example. But what don't we know? The answer to that question is big enough to fit inside the Grand Canyon. Here are a few.