This is so hard. Mine changes with my mood, genre, etc. ad naseum. Yesterday by the Beatles is one I always enjoy. 7 by Prince and the New Power Generation blows me away with regularity because of the depth of the religion in a pop piece to say nothing of its musical layering and ethnic feel. Man, there're too many good songs out there to choose. you might as well ask me what my favorite internal organ is; without any I am dead, so i couldn't choose. Er, yeah, music means a lot to me.
Well, I don't know if you'd call it a song, more like a piece of music... but for me it's Rachmaninov's Rhapsody on a Theme of Paganini. I could listen to it all day every day...
Featured in Somewhere in Time, the ultimate love story. Christopher Reeve, Jane Seymour... I could start bawling right now!! :sad