The Ultimate MC - American History Information Guide and Reference

MC can be used:

(along with emcee), as the abbreviation for Master of Ceremonies
in reference to MobCulture, a browser-based click-through MMORPG set in the near future.
(along with M.C.), as the British military decoration - the Military Cross
as the ccTLD for Monaco, .mc
to mean Microcomputer, though the term is becoming obsolete. (The term "microcomputer" has largely been superseded by "Personal computer".)
as a prefix to mean "son of", as in McCarthy, see also Mac and patronymic.
(along with m/c), as the abbreviation for machine
as the abbreviation for Member of Congress
(along with m/c), as the abbreviation for the city of Manchester in England
as an abbreviation for the Midnight Commander file manager, a Norton Commander clone for Unix.
as an abbreviation for motorcycle club.
as an abbreviation for musicassettes, a term for compact audio cassettes pre-recorded with music.
as an abbreviation for master cylinder.
as an abbreviation for Marin Catholic.

Your American History Reference Guide! - MC