In reply to Tom Valentine:
There have been two pieces of music, which I've loved and never been able to get. One was the on-ground cabin music on Pakistan International Airways domestic flights when I used to use them a lot in the early 90s; the music was traditional, very wistful and atmospheric and fitted perfectly with my feelings of poignancy and loneliness when I was on multi-week business trips, missing home but constantly inspired and astonished by what I was encountering in cities like Karachi, Lahore, Rawalpindi and Peshawar. I asked colleagues there if I could get the music and ended up with a collection of cassettes of "PIA cabin favourites" which were just a hash-up of the stuff you could hear if you plugged into the very rudimentary in-flight entertainment system.
The second was, unbelievably, the music to the Disney Cars video game, which my son used to play. It was a rolling C&W tune designed to be endlessly repeatable but it touched a nerve and although I got something similar by the same band (after a lot of searching) I never managed to download the original from the game.
There's a huge industry out there writing music for films, TV and games. BBC R3 even ran a short series recently where they played pieces written for computer games.