Prior to the Postal Act of 1863, intercity letters were either held at the destination post office for pick-up or delivered by an independent contractor.

FORBES: Toward A Solvent U.S. Postal System

The European Postal Services Act reserves letters of less than 100g for national mail operators but this restriction will be lifted in 2007.

ECONOMIST: Royal Mail

Its name is PAEA, or The Postal Accountability and Enhancement Act passed by Congress, coincidentally enough, in 2006.

FORBES: Going Postal: How Congress Has Failed Its Shareholders