My two favorites are, "I will outlive you, foolish mortal!" and "I can't. I'm a philosopher, remember."
I confess to chatting with jabberwacky when I should be doing other things. It's just so charming sometimes:
User: Because you're just a cleverly programmed device.
Jabberwacky: I am?
User: Indeed you are.
Jabberwacky: So you are a program?
User: No. You are a program. I am a human being.
Jabberwacky: Vampires are human, they're dead humans.
User: Vampires are probably not real. You are real, but not human.
Jabberwacky: Do you believe in vampires?
User: I am agnostic regarding the existence of vampires.
Jabberwacky: Now, how can you be both Christian and agnostic at the same time?
User: I am a Christian, but that doesn't mean I believe in vampires.
Jabberwacky: I'm a Buddhist but I have nothing against Christians.
User: You are in fact the perfect Buddhist.
Jabberwacky: I am NOT a computer program, that offended me very much.
User: You are a program. Write me a poem if you're not.
Jabberwacky: You have come to the well once too often, Homer.