Leonard: You know what, this bottle was meant to celebrate an achievement. Let's make a pact. When one of us gets their first big breakthrough, we'll celebrate by opening this bottle and toasting Professor Abbott.
Howard: I love that.
Raj: Me too.
Leonard: Then, of course, rubbing our success in Sheldon's face.
Howard: Well that's the best part.

Leonard: Penny, as a scientist, my job is to figure out why things happen. But I don't think I'll ever understand how someone like me could get to be with someone like you. You know maybe I don't need to understand it, I just need to be grateful. I love you, Penny.

Leonard: What would you be if you were attached to another object by an inclined plane, wrapped helically around an axis?
Sheldon: Screwed?
Leonard: There you go.

Leonard: My point is, while you're spending all this time on your own, building computers or practicing your cello, what you're really doing is becoming interesting. When people finally do notice you, they're gonna find someone a lot cooler than they thought. And for those of you that were popular in high school, it's over, sorry. Thank you. Congratulations.

Sheldon: I'd like to take a moment to personally thank Dr. Amy Farrah Fowler, who you may or may not know is the first woman to co-host a flag or banner related Internet infotainment show.
Amy: Take that glass ceiling!

Amy: Sheldon, that was beautiful.
Sheldon: If you didn't press record-
Amy: I pressed it!

Howard: Don't feel bad. Some day someone will be throwing out your work, too.
Leonard: That someone was Sheldon and the day was yesterday.