My brother was in town for a conference and left on an early flight this morning. I woke up a bit when I heard the sound of spoon on cereal bowl, a very distinctive and penetrating sound. I sat bolt upright sometime later when I heard three successive sproings, like very loose piano strings being plucked.
It turned out they were the sound wire hangers springing back into shape. I had washed some of his t-shirts and hung them to dry on a very high rod in his room. He couldn't reach the hangers themselves, so he had eventually just pulled on the shirts until they came off. It was a very odd sound to wake up to.