Why don't we take turns posting some of the great lines from Star Trek's history ? Don't forget to mention which character and which movie or episode and series the quote is from.
I'll go first:
I've done far worse than kill you, Admiral. I've hurt you. And I wish to go on hurting you. I shall leave you as you left me, as you left her; marooned for all eternity in the center of a dead planet... buried alive!
- Khan, TWOK