The JR Yamanote line plays a different "jingle" for each station. As I understand it, the idea is to make it easy to determine when you arrive at your station.
After visiting Japan in 2007 and taking the line from the hotel to the office I had the Ebisu tune as my SMS tone for quite some time.
They had station-specific melodies back in the early 1990s when I was a student. I wonder if these are updated versions of the same melodies or new compositions.
I don't know why, but this is pretty soothing to listen to while working