Reporters have taken the undercover route from slaughterhouses and chicken- and pork-processing plants to fast-food chains and supermarkets to understand the system.

Journalists from the United States and Australia get inside the post-Civil War practice of recruiting Pacific Islanders to work the world's non-U.S. plantations on extended contracts of indenture.

Reporters have worked as guards or gotten themselves arrested -- sometimes with the aid of authorities and sometimes without -- to investigate conditions inside prisons and jails.

Since the 1870s, journalists have been posing as patients or attendants to expose horrid conditions and treatment inside mental hospitals. Nellie Bly, incidentally, was not the first.