I was reading the first issue of Weird Science, the great EC comic book, the other day. The first story in the first issue told the story of a guy who gets hit with a shrinking ray. As he becomes ever smaller, he goes through a series of universes. So each of them is like a little, tiny universe in your fingernail. Don't know if Harold ever read Weird Science. Doubt it, actually. But, wow, cool.
Chris