Limousine by Brand New, one of the most powerful and haunting songs in my opinion. I get chills every single time I listen to it.
It's about a seven-year-old girl who was killed by another driver who was drunk. She was coming home from a wedding and, according to her mother, her last words were: 'This is the best day of my life!' Not only did she die in the car crash, but so did the limousine driver. Their names were Katie and Stan. It's an extremely sorrowful story. It's said that her head was decapitated.