The sheet of paper that Jimmy writes on on the bus is the real sheet that Eminem wrote "Lose Yourself" on. The sheet of paper sold for $10,000 on an eBay auction.
Eminem improvised his lyrics and changed the lyrics in the battle rap scenes. This threw off the other rappers.
"Lose Yourself", recorded especially for 8 Mile, was the first rap song to win the Academy Award for Best Original Song, which it did in 2003.
Eminem was unable to accept his Academy Award in person. He felt so sure another nominee would win that he did not bother to attend the ceremony. Instead he was sleeping, while his daughter watched cartoons the night he won.
In the movie, Jimmy's mother states he got his nickname Rabbit because, as a child, he had big teeth like a bunny rabbit. In real life, Eminem's relatives called him "Mickey," in reference to "Mickey Mouse," for the same reason.