We used to remove the bullet from .22 cartridges, plug up the bullet with wax, and shoot it (now a blank) at the closed bedroom door. Naturally, my mother wasn't home when we did this, and we'd scrape the little blobs of wax off the door when we'd finished.

One day, Mom decided to repaint the door. At dinner that evening she said, "I tried to paint you boys' bedroom door today, but there's something wrong with the paint. It won't stick to some spots."

Silence and noncommital answers were given....