Leonard: Sheldon, why are you walking everywhere?
Sheldon: Just get a horse. I had a horse. It got hit by a train.
Leonard: Get another one.
Sheldon: I can't just replace Chauncey. I'm still in the grieving process.

Penny: You know, you're the only person who could win the biggest prize in science and still be upset about it.
Sheldon: It's just all the times I thought about winning, I never thought about how it would ch-- affect my life. I'm sorry, I'm genuinely concerned about your liver.

Sheldon: If I'd known this was about time travel, I'd have watched this much sooner.

Sheldon: No, I'm not okay. I'm wearing borrowed pants, I don't have ID, and one of the officers here won't stop calling me chicken legs.

Sheldon: Leonard, let me tell you something. Personal robots cannot get here soon enough.

Sheldon: Oh apple juice stay where you are.

Sheldon: Just pick out anything? Maybe at the same time we can pick out a new suit for him without knowing his size, or pick out his career for him without knowing his attitude, or pick out a new breakfast cereal without knowing his fiber requirements or his feelings about little marshmallows.

Sheldon: Cathedra mea, regulae meae. That's Latin for my chair, my rules.

Sheldon: All right. What would you like me to do first?
Howard: Well, I thought I'd start you off by polishing my belt buckles.
Sheldon: Oh. By all means. When I was a boy, I would polish my Mee-Maw's silver. And she would entertain me with stories about growing up in Oklahoma. Interesting woman. You know, she once killed a prairie dog with a gravy boat.
Howard: That's nice.

Sheldon: I am facing a great deal of work. And I do like things better when famous people also like them.

Sheldon: Hang on, hang on! We're smart, we can figure this out. Okay, so: Mary and Beverly can't be together. Uh, Alfred and Beverly can't be together. Leonard and I can't be together. Now, I could be with Alfred but I don't like his face.

Amy: Are you excited to see your son walk down the aisle?
Alfred Hofstadter: Yes, I am. I'm just feeling a little guilty about all the trouble I've caused.
Mary Cooper: Oh, so am I.
Sheldon: You made God sad today, Mom.

Penny: Hi.
Sheldon: Hello.
Penny: What are you doing?
Sheldon: Oh, Leonard's mad at me, so I'm making him lemon bars.
Penny: Does he even like lemon bars?
Sheldon: Not really. But I'm mad at him, too, so lemon bars it is.

Sheldon: Which side of the bed would you prefer?
Amy: Doesn't matter to me. Your choice.
Sheldon: No, no, we're living together now. Everything's equal. I know that I have a tendency to be controlling, so I would rather you choose.
Amy: Well, Sheldon, I really appreciate that, but these things mean more to you than they do to me, so whatever you want.
Sheldon: Well, clearly, it's not whatever I want, because what I want is for you to make this decision, and you refuse to do that.
Amy: Well, I'm not refusing. I'm just trying to be considerate.
Sheldon: Like when you let me get those shoes with the wheels on the bottom, and then watched me roll right into traffic?

(Amy enters from the ensuite bathroom after Sheldon overheard her pre-bed routine)
Amy: Why'd you switch sides?
Sheldon: Be grateful I'm still in the room.