Penny: So are the rest of the guys meeting us here?
Leonard: Oh, yeah, no. Turns out that Raj and Howard had to work, and Sheldon had a colonoscopy and he hasn't quite bounced back yet.
Penny: Ooh, my uncle just had a colonoscopy.
Leonard: You're kidding. Well, then, that's something we have in common.
Penny: How?
Leonard: We both have people in our lives who ... want to nip intestinal polyps in the bud.

Penny: Okay, well, you know, it's just me. I'm still getting over this break-up with Kurt, and this thing with Doug would be just rebound sex.
Leonard: Ugh, don't get me started on rebound sex.
Penny: It's just, it's my pattern. I break up, then I find some cute guy, and then it's just thirty six meaningless of ... well, you know.
Leonard: I'm not sure that I do. Um, is that one thirty-six hour experience, or is it thirty six hours spread out over say, one ... glorious summer.
Penny: No, it's usually over a weekend, and trust me, you do not feel good after it.
Leonard: Well, chafing, right?
Penny: Emotionally.
Leonard: Of course, yeah, emotional chafing.

Penny: Are you sure you don't want to go to the emergency room?
Leonard: No, no, I'm okay, it's stopped bleeding.
Penny: I know, but you did throw up. Isn't that a sign of a concussion?
Leonard: Yes, but I get car sick too, so...
Penny: Okay.
Leonard: Sorry about your car, by the way.
Penny: Oh, no, it's fine, you got most of it out the window.
Leonard: The poor guy on the bike.

Penny: Leonard?
Leonard: Yeah.
Penny: Was this supposed to be a date?
Leonard: This? No. No, of course not, this was just you and me hanging out with a bunch of guys who didn't show up, because of work and a colonoscopy.
Penny: Okay, I was just checking.
Leonard: When I take a girl out on a date, and I do, she knows she’s been dated. Capital D. Bold face, underline, like Day-ted.
I think I might have a little concussion, I'm going to go lay down for a while. Good night.

Sheldon: I couldn't sleep knowing that just outside my bedroom is our living room and just outside our living room is that hallway and immediately adjacent to that hallway is [Penny's messed up apartment]!
Leonard: Do you realize if Penny wakes up there's no reasonable explanation to why we are here?
Sheldon: I just gave you a reasonable explanation.
Leonard: No, no. You gave me an explanation. Its reasonableness will be determined by a jury of your peers.

Leonard: You convinced me. Maybe tonight we should sneak in and shampoo her carpet?
Sheldon: You don't think that crosses a line?
Leonard: Yes! For God's sake, Sheldon, do I have to hold up a sarcasm sign every time I open my mouth?
Sheldon: You have a sarcasm sign?

Sheldon: You do understand that our efforts here will in no way increase the odds of you having sexual congress with this woman?
Leonard: Men do things for women without expecting sex.
Sheldon: Yeah, those are men who just had sex.
Leonard: I'm doing this to be a good neighbor. In any case, there's no way it could lower the odds.

Sheldon: I have to say, I slept splendidly. Granted, not long, but just deeply and well.
Leonard: I'm not surprised. A well known folk cure for insomnia is to break into your neighbor's apartment and clean.
Sheldon: Sarcasm?
Leonard: You think?

*Leonard tries to slip a note under Penny's apartment door*
Penny: Hi.
Leonard: Oh.
Penny: What's going on?
Leonard: Um, here's the thing. (Reads from the note.) Penny, just as Oppenheimer came to regret his contributions to the first atomic bomb, so too I regret my participation in what was, at the very least, an error in judgment. The hallmark of the great human experiment is the willingness to recognize one's mistakes. Some mistakes, such as Madame Curie's discovery of Radium turned out to have great scientific potential even though she would later die a slow, painful death from radiation poisoning. Another example, from the field of Ebola research-
Penny: Leonard.
Leonard: Yeah.
Penny: (hugs him) We're okay.

Leonard: I love cheesecake.
Sheldon: You're lactose-intolerant.
Leonard: I don't eat it. I just think it's a good idea.

Leonard: (Helping Althea with the crossword puzzle) One across is Aegean, eight down is Nabokov, 26 across is MCM, fourteen down is-- move your finger, phylum, which makes 14 across Port-au-Prince. See, Papa Doc's capital idea, that's Port-au-Prince. Haiti.

Leonard: Our babies will be smart and beautiful.
Sheldon: Not to mention imaginary.