Leonard: It's hard sometimes. Everywhere you go, guys hit on you, even if I'm standing right there. And they're all taller than me. Why is everyone taller than me? You know what, this is all in my head. It's my problem, not yours.
Penny: Leonard, why do you always do this? Listen to me, you're the one I'm with. You know I love you. So will you please relax, because you're driving me crazy.
Leonard: You know that's the first time you ever said you love me.
Penny: Yeah.
Leonard: We're just supposed to pretend it's not a big deal?
Penny: That's exactly what we're gonna do, because you're about to make me cry. And we both know if I start crying, you're gonna start crying.
Leonard: You're right, I should go.

Sheldon: Woman, you are playing with forces beyond your ken.
Penny: Yeah, well your Ken can kiss my Barbie.

Raj: [to Amy] If you were having Sheldon's baby, would you really want him in the room?
Penny: Yeah, if he's in the room when they're making the baby, I'll give you $10.

Leonard: If I take it off, Sheldon wins.
Penny: Sweetie, every night you don't kill him in his sleep, he wins.

Sheldon: You may not realize it, but I have difficulty navigating certain aspects of daily life. You know, understanding sarcasm, feigning interest in others, not talking about trains as much as I want. It's exhausting!

Sheldon: (Playing hackey sack) One, two, three, four, five, six, seven, eight. Drat. I'm never going to get to forty-three again. One, two, three, four. Rats.

Penny: Hey! Shouldn't you be out with your gang spray painting equations on the sides of buildings?