The use of Led Zeppelin's "Babe I'm Gonna Leave You" over the final scenes of the Season 3 finale. A scene that was already tense and heartbreaking is doubly so due to the haunting nature of the song's ending over the final shot: Haley's Crackerjack bracelet drifting to the top of the pond, as Nathan has dived in to the submerged limo to save Cooper and Rachel, and is rapidly running out of air. The use of the music was also momentous: prior to this episode, Led Zeppelin had never before licensed their songs for network television. The only time it had happened before was on cable, for The Sopranos. Not only was the music awesome, it was history-making!