From the end of the Steve Martin episode:
Statler: Well, that was different.
Waldorf: Yep. Lousy...
Both: ...but different!
From the George Burns episode:
Waldorf: Bravo, bravo!
Statler: Why are you yelling 'Bravo!'? Did you like it that much?
Waldorf: Nope. Friend of mine, Joe Bravo; he's sitting in the third row. Bravo! Bravo!
Both: Up here!
From the end of the George Burns episode:
Waldorf: How do they do it?
Statler: How do we watch it?
Waldorf: Why do we watch it?
Statler: *turning to camera* Why do YOU watch it?
From the end of the Bob Hope episode:
Waldorf: Doesn't Hope usually sing "Thanks for the Memories?"
Statler: Why would he want to remember this?
From the end of the Alice Cooper episode:
Waldorf: So, that was Alice Cooper?
Statler: You should see his sister, James Fenemore!
From the end of the Liberace episode:
Statler: Finally we've seen them do a good show!
Waldorf: Good, can we please stop coming now?
From the end of the Paul Simon episode:
Statler: Say you old fool! You slept through the show!
Waldorf: Who's the fool? You watched it!
Here's a classic zinger from Waldorf. After Statler makes a remark Waldorf replies, "Have you ever thought of checking into the Home for the Chronically Strange?"
And finally, after the Mahna-Mahna number in the Juliet Prowse episode...
Statler: The question is, what is a Mahna-Mahna?
Waldorf: The question is, who cares?
-Kim