Leonard: So, tell us about you.
Penny: Um, me? Okay - I'm a Sagittarius, which probably tells you way more than you need to know.
Sheldon: Yes - it tells us that you participate in the mass cultural delusion that the sun's apparent position relative to arbitrarily defined constellations at the time of your birth somehow affects your personality.
Penny: ... participateinthewhat?
"Hello, insufficiently intelligent person."
"Oh, I'm sorry. Did I insult you? Is your body mass somehow tied into your self worth?"
"You'd hit particulate soil in a colloidal suspension. Mud."
"What part of an inverse tangent function approaching an asymptote don't you understand?"
"Maintaining five friendships promises to be a Herculean task, so I'm going to have to let one of you go."
"I can't keep your secret, Penny. I'm going to fold like an energy-based de novo protein in conformational space... like a Renaissance triptych... like a cheap suit."
"Hello? I know you're out there. I can hear you metabolising oxygen and expelling carbon dioxide!"