Outside arcade:
Not from a game, but by FAR my favorite Atari 8-bit song:
http://www.youtube.com/watch?v=tiX8Ba2L4u0(this is faster than I'm used to though, the Euro 50 Hz Atari's played this slower...)
Esp. the part from 1.09 was impressive at those days !

I still love a load of Mario music, IMHO still some of the best in the business..
Arcade related...hmmm, that's hard but I think it's the Ms.Pac intermissions Act 1 & 2. (3 was a real disappointment IMHO)
http://www.youtube.com/watch?v=GzZysHkdC6UAs you guys know I love BASS and this has about the BASS sound in any arcade music....only the real hardware and the real cab produce exactly the right "feeling" and sound.... !

Also the "pop" sound is EPIC...
Act 2, the chase is my favorite, followed by Act 1. Act 3 is a real disappointment both musically and the animation itself lacks the "surprises" of the first two acts...