Tennessee Valley Authority

Wikipedia

The TVA supplies power to all of Tennessee and parts of each bordering state. It is federally-owned, but independent and funded by its own revenue.

It's an interesting case study of an organization operating in the public interest, yet independent from other government bodies.

I learned about it during a Sociology class on work and organizational structure, where one of the readings was Philip Selznick's 1953 TVA and the Grass Roots: A Study in the Sociology of Formal Organization