When I was five or six years old, "The Roy Rogers Show" was a staple of Saturday morning TV. One night I dreamed that Pat Brady, Roy's Jeep driving sidekick on the program, was driving his Jeep down a dirt road when he came upon an old woman sitting at a spinning wheel. As he talked with her, her eyes and mouth transformed themselves into triangles, then squares, then back to triangles again. It would be funny now, but it was terrifying for a kid.

Much later, when I was still married to my first wife, we both overslept by about fifteen minutes because we were both dreaming that the sound of our new alarm clock was the sound of an alien spaceship. I wouldn't go so far as to say we were having the same dream, but we both incorporated the alarm's sound into our dreams and both interpreted it as the sound of a spaceship.