Call me a cynic if you want, but while I endorse the message of civil rights, I've always had some problem with his speeches. What I've always been impressed with, however, was the letter he wrote when he was imprisoned in Birmingham to a group of white clergymen who disagreed with his methods. Unable to give a speech to a sympathetic audience from his cell, he had to choose his words very carefully, and the result is a masterful defense of nonviolent protest and an articulation of the elements that can justify civil disobedience and its manner of execution.
The video below is a verbatim dramatization of that entire letter, performed by Corey Jones playing the role of Martin Luther King, Jr. (starts at about the 4 minute mark).
That's what they get for writing a letter to a man who's got lots of education and plenty of time to respond while sitting in jail :)