[Sheldon is trying Howard's driving simulator - with disastrous results]
Leonard: How did you manage to get on the second floor of the Glendale Galleria?
Sheldon: I don't know, I was on the Pasadena Freeway, missed my exit, flew off the overpass and...one thing led to another.
[Screeching tires are heard from the simulator, followed by a crash and barking and meowing]
Leonard: Awwwwww, the pet store��
Sheldon: Remind me to compliment Wolowitz on the software, it's amazingly detailed.

[Sheldon suggests taking up jogging]
Penny: Have you ever run before?
Sheldon: Certainly! I've run from bullies, dogs, angry chickens and one particularly persistant P.E. teacher determined to bend me over and give me a scoliosis test.
[Raj whispers in Howard's ear]
Howard: You're right, Penny jogs. Maybe you guys can run together.
Sheldon: That's an excellent idea! If we chat it will create the illusion of time going faster!
Penny: No, it won't.

[The group is discussing Raj's new girlfriend possibly taking advantage of him]
Sheldon: I actually have information about Raj that would be helpful with this discussion. [resumes eating]
Leonard: [long pause] Could you tell us?
Sheldon: Let's see��[rolls dice] Snake eyes. Sorry, bud.
Penny: [points to dice] Wait, hang on. Doubles. Roll again.
[Sheldon does so]
Sheldon: ��Okay, get this. [Penny and Leonard exchange looks of annoyance] It doesn't matter if he's showering her with gifts. Because the Koothrappalis are vastly wealthy.
Penny: What do you mean "vastly wealthy"?
Sheldon: Well, wealthy means a lot of money, and vastly means even more��I'm not sure what's tripping you up.
Leonard: Oh, I know they have money. I don't think it's that much.
Sheldon: No, you're wrong. See, as you know, a few years ago, I achieved one of my lesser dreams and became a Notary Public. From time to time, I notarized banking documents for Raj. The Koothrappalis aren't just rich. They are Richie Rich rich.
Penny: Well, so how much is that?
Sheldon: About halfway between Bruce Wayne and Scrooge McDuck. ($18.5 billion)
[The others look shocked]
Howard: [outraged] What the hell! The last time we went to the zoo, that son of a bitch made me buy him a churro!
Leonard: Listen guys I don't meant to be rude, but I need to go call Raj's sister, who I love so much. So vastly much.

[the guys are playing Klingon Boggle]
Howard: I have "chor" [Klingon for "belly"]
Sheldon & Raj: Got it.
Howard: "neHmaH" [Klingon for "neutral zone"]
Sheldon & Raj: Yep.
Howard: And "Kreplach".
Raj: Hold on a second, "Kreplach"?
Howard: Yeah.
Raj: That isn't Klingon, it's Yiddish for a meat-filled dumpling!
Howard: Well, as it turns out, it's also a Klingon word.
Leonard: Really? Define it.
Howard: Kreplach: a hearty, Klingon��dumpling.
Raj: Judge's ruling?
Sheldon: [makes thumbs-down gesture] bIlughbe' [Klingon for "you are not right"]

[The guys are playing Mystic Warlords of Ka'ah]
Raj: Water demon.
Howard: Ice dragon.
Leonard: [victorious tone of voice] Lesser Warlord of Ka'ah!
Sheldon: Not so fast! Infinite Sheldon.
Leonard: Infinite Sheldon?!
Sheldon: Yes, Infinite Sheldon defeats all other cards, and does not violate the rule against homemade cards because I made it at work.
Leonard: Do you understand why people don't want to play with you?
Sheldon: No. Although it's a question I've been pondering since preschool.

[the guys are reading responses to Sheldon's lecture]
Leonard: I found another Tweet from a student at Sheldon's lecture: [from his phone] "Dr. Cooper has taken a relatively boring subject and managed to make it completely insufferable. Plus, he looks like a giant insect."
[Raj laughs]
Howard: Listen to this one: [from his phone] "Does Einstein's theory explain why time flies when you're having fun, but when you're listening to Dr. Cooper, it falls out of the sky, dead?"
[Howard and Leonard laugh]
Raj: [while on a laptop] Ooh, somebody took pictures and uploaded them to their Flickr account.
[Howard and Leonard have a look on the laptop]
Leonard: [amazed] Wow. How do you get an entire lecture hall to flip you off at the same time?
Howard: Apparently, if you're Sheldon, all you need to do is turn your back.
[Penny enters]
Penny: Hey, Leonard, is your wi-fi down? I can't get on.
Leonard: Oh, Sheldon changed the password. It's now "Penny is a freeloader"��no spaces.
Penny: [typing on her phone] Thanks. What are you guys doing?
Leonard: Sheldon gave a lecture at the university tonight [and] we're reading the reviews.
Penny: Oh, how'd he do?
Howard: Well, picture the Hindenburg meets Chernobyl meets Three Mile Island meets Tron 2.
Penny: That bad, huh?
Leonard: [going to Penny with his phone] Read this woman's Tweet.
Penny: [reading from Leonard's phone] "Listening to Dr. Cooper's made me want to start cutting myself again."

[Upon hearing that Leonard, Wolowitz, and Raj are upstairs in the new girl's apartment]
Penny: Typical.
Sheldon: It's axiomatically atypical. Up until recently they did not know Alicia, and had no encounters with her in her previous location. They never went upstairs to visit the former tenants. So your characterization of their behavior as typical is demonstrably fallacious.
Penny: [referring to his earlier impersonation of Admiral Ackbar] OK, now I see the squid head.

[While Sheldon is listening to a tape, Penny comes from behind and touches his shoulder, which scares him.]
Penny: Sorry, Sheldon. Do you have a second?
Sheldon: A second what? Pair of underwear?
Season 2

[after several scenes where Penny does something of which Sheldon approves, and gets a piece of chocolate in return]
Leonard: OK. I see what you're doing.
Sheldon: Really.
Leonard: Yes. You're using chocolates as positive reinforcement for what you consider correct behavior.
Sheldon: Very good! Chocolate? [while offering the box to Leonard]
Leonard: No! [moves away]

[Penny knocks on the door]
Penny: Merry Christmas!
Leonard: Merry Christmas!
Penny: How's your leg?
Leonard: Very good. Thanks for asking. Come on in.
Sheldon: Oh good, Penny, you're here to exchange gifts. You'll be pleased to know that I'm prepared for whatever you have to offer.
Penny: [handing Sheldon his present] Ok, here.
Sheldon: Hmmm. [starts to open his present] I should note, I'm having some digestive distress, [Leonard shakes his head no] so if I excuse myself abruptly, don't be alarmed. [completes opening his present] Oh! A napkin.
Penny: Turn it over!
Sheldon: [becomes weak at the knees and has to sit down as he reads] "To Sheldon. Live long and prosper. Leonard Nimoy."
Penny: He came into the restaurant. Sorry the napkin's dirty, he wiped his mouth with it.
Sheldon: [gasps] I possess the DNA of Leonard Nimoy?!
Penny: Well��yeah, I guess. But look, he signed it!
Sheldon: [visibly shaking] Do you realize what this means?!?! All I need is a healthy ovum and I can grow my own Leonard Nimoy!
Penny: Okay, all I'm giving you is the napkin, Sheldon.

[Sheldon has joined Penny, Bernadette and Amy Farrah Fowler on their girls night out at a bar]
Penny: Sheldon, have you ever kissed a girl?
Sheldon: Other than my mother, my sister and my mee-maw, no. But in the interest of full disclosure, I was once on a bus and had to give mouth-to-mouth to an elderly nun who passed out from heat exhaustion. Every year I get a Christmas card from her, signed with far too many X's and O's.
Bernadette: That doesn't count! Aren't you even a little curious?
Penny: Yeah, you're a scientist, where is the curiosity?
Amy: I'm available for experimentation [turns towards Sheldon and puckers up]
Sheldon: Thank you, but not necessary. We know everything there is to know about kissing. It requires 34 facial muscles and 112 postural muscles
Amy: Oh blah blah blah. Give me some sugar, bestie. [turns to Penny and kisses her, all three girls start giggling]
Sheldon: I'm certainly glad no one said they were curious about Aztec human sacrifice.