My favorite line is everything that Oscar Wilde has ever said or written. Just... all of it. That man was the master of quips, wit, and dry humor. No one else comes close.
Examples:
"Some cause happiness wherever they go; others whenever they go."
"Work is the curse of the drinking classes."
"Bigamy is having one wife too many. Monogamy is the same."
"A little sincerity is a dangerous thing, and a great deal of it is absolutely fatal."
"If you want to tell people the truth, make them laugh, otherwise they'll kill you."
"The public is wonderfully tolerant. It forgives everything except genius."
"The world is a stage, but the play is badly cast."
I could post about Oscar Wilde all day. He was so awesome that he was played by Stephen Fry. And, you know, was a literary genius. But Stephen Fry. Also, he was writing all of this in the Victorian era.