I love RDR, and particularly this song when you enter mexico:
http://www.youtube.com/watch?v=7IkvAb6THQY
That was one of my favourite moments too.
There was a similar situation in the excellent DLC Undead Nightmare, with one of the coolest songs ever. The timing and atmosphere of it was spine tingling.
[video=youtube;A1iM3HRXlmU]http://www.youtube.com/watch?v=A1iM3HRXlmU[/video]
