The song Glycerine, of the post-grunge band Bush, is probably the song that has had the most impact on my life. I was 17 years old when I discovered this song. I had just moved out of my parents' place to go to college and started dating the woman that would later become my wife.
Even today, 12 years later, this might still be my all-time favorite song. I just listened to it ... twice. Nostalgic!