Usually, I sleep like the dead. It's the sleep of the righteous, of course. On occasion, however, if I'm having trouble dropping off it's not my demons keeping me awake, but more than likely a song.
It's infuriating when you get a tune buzzing round your head in the dead of night. They've varied from things like Shine On by the House of Love ('shi-shi-shi-shine ooooooooonnn'), to the brief Chopsticks excerpt heard in the 'Daddy or chips' advert some years back - it kept me awake for about three months until I was almost in tears - to the opening bars of Doin' The Do by Betty Boo.
Other refrains:
'Horace Wimp!/This is your life/Go out and find/Yourself a wife!', then 'Horace/Horace/Horace/Horace/Horace, Horace, Horace, Horace, Horace', etc., plus the squeaky violins, until the alarm went off.
'Everybody have fun tonight/Everybody Wang Chung tonight'.
The picky guitar intro intro to Goodbye by Mary Hopkin.
The middle eight from 10538 Overture. What is it about ELO?
The theme from Bergerac, with an image of that spinning Jersey. That could be a deep-rooted anxiety.
Karen Carpenters low bits from various songs. Mum and Dad's parties.
There are more, but if I dwell, I may not sleep tonight.
