Campanella Effect

The sense of almost boyish enthusiasm that comes over middle aged men when pursuing a hobby that requires expensive stuff and leaves non-hobbyists scratching their heads to figure out why it's so damned important. (Derived from Roy Campanella's observation about baseball: "You got to have a lot of little boy in you to play this game.")

When Jerry began talking about model railroading, it was easy to see the Campanella Effect in action.