The Straight Dope has more on this: http://www.straightdope.com/columns/read/3063/why-is-the-letter-z-associated-with-sleep http://www.straightdope.com/columns

The Straight Dope has more on this: http://www.straightdope.com/columns/read/3063/why-is-the-letter-z-associated-with-sleep http://www.straightdope.com/columns/read/3063/why-is-the-let...