I've had a melody from the theme song of a BBC TV series called "The Changes" stuck in my head for years. Somehow this tune has been swirling around in my head since I was 7, which is when I first saw the TV show. When I finally found the theme music though, it's not quite as I remembered it -- somehow I'd increased the role of the initial repeating synth-loop and made that the main part of the tune. I much prefer my own version, as the original sounds weak, and not nearly as sinister as I remember the show being.

The theme music was by Paddy Kingsland, who also wrote the theme songs for some "Dr. Who" shows, and also "Hitch Hikers Guide to the Galaxy". Classics.