Since posting my piece on tunes that get stuck in your head I have been amazed to discover that it is a well-known phenomenon and, like all the best minor mental disorders, there's a German word to describe it: Ohrwurm (literally Earworm)
There's an entry in Wikipedia. People have even written academic papers and newspaper articles on the subject:
The last site describes 'cutting-edge earworm research' being carried out at the University of Cincinnati and even offers a virtual clinic outlining useful strategies for getting a song unstuck (from which I derived a grain of consolation in seeing my own remedy listed)
Which all goes to show that whatever you can possibly imagine it already exists somewhere on the internet.