The National Broadcasting Company (NBC) first used a peacock in its logo in 1956. The peacock had 11 feathers and was created to showcase the use of color on television. The original peacock was used until 1961 when it got replaced with an update that retired in 1975. The peacock returned to the logo in 1979.
The current more stylized verison of the logo was created in 1986 and counts only six visible feathers. The body and head of the peacock are 'drawn' by using negative whitespace resulting in a very sophisticated logo.
For more information, please see: http://en.wikipedia.org/wiki/NBC_logos