I don't think any song has that effect on me, but I have some good candidates... let's share some, starting with the classics and most know and then going to some unknown ones
A song called "Cry" from Mariah's new album, ironically enough. I was fine listening to it, but once it ended, I just bawled my eyes out. No sobbing - absolute bawling. Hahaha! I was a hot mess. Yeah - I'm a very emotional person...