Here is a word cloud of his "I Have a Dream" speech on wordle.net.

YouTube has several videos of him giving speeches, various tributes, and plenty of interviews with pundits talking about him. This one is a brief clip from the last speech he gave. His timing, cadence, and intonation are amazing. I also like the camera angle.

There are so many powerful quotes from this eloquent orator. Here's one my favorites.

Start celebrating today on his actual birthday!