Many years ago I worked in a cheap, two-story office building. My programming required me to go up and down the staircase a lot. It was a narrow staircase in a wooden building, but there was one simple conceit that gave the stairs an airy feeling: the ceiling above the stairs was flat, which meant that you could touch it at the top of the stairs, and it hung way above you (making it hard to clean) at the bottom. The staircase walls were painted off-white, and the ceiling was acoustical tile.
As I walked up and down those stairs, I often tossed a sharp pencil up and caught it. (We used pencils in those days.) A hard throw would make the pencil bounce off the ceiling at a crazy angle. A careful toss from a lower stair (there were seventeen stairs), and the pencil would sail way up, then float back down for an elegant catch.
One day, I tossed a pencil and it just kissed the ceiling. And it stuck there, at a slight angle, its point buried in the acoustical tile. It was more than a dozen feet above my head; there was no easy way to retrieve it. I just left it there.
Eight years later when I visited the building, my pencil still hung from that ceiling.