The glyph/code spells out RESET.

Olivia: Did I just step on a peanut?
Astrid: You're lucky that I convinced (Walter) not to use shrimp.

Nina: Maybe you can ask Walter if he remembers what group the boy was in. I mean, that may help.
Astrid: Of course. Uh, Walter, did you hear that?
Walter: (on the earpiece) Yes. Her voice goes right into my inner ear and rattles around like razor blades. Of course I heard her. Tell her to go...
Astrid: He said that he is not sure, but, uh, thank you for the suggestion.
Walter: I--I did not say that.
Nina: Walter has said many things to me over the years, but "thank you" was never one of them.

Walter: Claire, will you please man the cameras in my absence?
Astrid: Really? "Claire"? That doesn't even start with an A.

Walter: If you don't mind, I think I should urinate before we leave. Don't worry, I've packed us sandwiches.

Walter: Mysophobia... I haven't had an attack in years.
Olivia: It's curious, don't you think? The things that we see, that we investigate, and you don't bat an eye, and some harmless germs make you shake in your boots.
Walter: I suppose it is. Elizabeth, my wife, used to say I was a man of contradictions.

Walter: You have the ability to gather and direct the kind of power we need.
Cameron James: How?
Walter: Well, just like in the highway. Once when you were a boy, you--you blew up a toaster oven with your mind because of an irrational hatred of raisin toast.
Cameron James: You ever had raisin toast?

Walter: You acted against all reasonable agreements and expectations. You behaved irrationally, with regard to only your intuition and instincts.
Olivia: I guess I did.
Walter: When I do that, people say I'm crazy. I suppose I've learned that crazy is a lot more complicated than people think.

Walter: An idea I got from the fight sequences in The Matrix.

The Matrix is a 1999 movie which is set in a virtual reality landscape and features several "wire-fu" combat scenes.

The Observer can be seen at Reiden Lake as Peter returns.