There is one song I can never listen to without getting goosebumps on my arms and tears in my eyes. Each and every time this song gets me. If I was allowed only one song, only one. This would be that song:

Barcelona - Freddie Mercury & Montserrat Caballé

This is a (semi) live performance in a huge open-air concert in Barcelona. Two voices, so different in style and sound, so perfectly blended together in a song of epic proportions.