It's not a song as such
It's a piece of classical music. It's called Adagio for Strings, and I'm sure pretty much everyone has heard it in one form or another.

Without saying exactly why, it's a very, very emotional piece of music that I first heard in Homeworld, and have done my best to avoid since as it sends me to a dark, dark place that requires much whisky to get me out of.
(Potty Jag har smör i min rumpspringa, Wed 3 Jun 2009, 19:05, 1 reply, 16 years ago)

Barber's Adagio for Strings?
I love that piece of music. Albinoni's Adagio In G Minor is a gorgeous piece of music as well.

While I was writing that, I was blasting out Infernal Dance from the Firebird. Now THAT is a choon.
/weird
( Lampito rise with the moon, go to bed with the sun, Wed 3 Jun 2009, 19:08, Reply)

To go further down the classical route
Bach - Fugue. I use it to test out speakers as it's a pain for most to recreate the lower organ notes properly. Get the right speakers, and you can use it to make people's intestines do odd things.

Sadly not listening to naything right now as I cba to reach over and switch on my speakers.
(Potty Jag har smör i min rumpspringa, Wed 3 Jun 2009, 19:13, Reply)