Fred Rodrigues Montenegro (born in Jaboatão dos Guararapes, Pernambuco, on July 11, 1965), known by the stage name Fred 04, is the leader, singer, guitarist and cavaquinho player of Brazilian band Mundo Livre S/A. He is the co-author, along with DJ Renato L, of the Mangue Bit manifesto, "Caranguejos Com Cérebros" ("Crabs With Brains"). He has a degree in journalism from the Federal University of Pernambuco. He made up his nickname '04' after the two last digits in his identity document.