Beastie Boys

Three MCs, and sometimes one DJ:

Mike D (Michael Diamond)
Adrock (Adam Horovitz)
MCA (Adam Yauch)

Plus, when it suits, Mixmaster Mike (Michael Schwartz).

The Beastie Boys originally formed in 1979 under the guise of The Young Aborigines. MCA joined in 1981, and their name changed to what it is today. Horovitz arrived later, and the core trio was born.

Initially a punk band, in 1984 The Beastie Boys released their first hip-hop effort, 'Rock Hard', via Def Jam. They supported Madonna in 1985 and released their debut album, License To Ill in 1986. The rest, as they say, is history.

Album discography:

License To Ill (1986)
Paul's Boutique (1989)
Check You Head (1991)
Ill Communication (1994)
Some Old Bullshit (1994)
The In Sound From The Way Out (1996)
Hello Nasty (1998)
The Sounds Of Science (double-disc compilation) (1999)
To The 5 Boroughs (2004)
Solid Gold Hits (best of) (2005)
The Mix-Up (2007)