Sheldon can now die happy. On this episode of The Big Bang Theory, he meets Stephen Hawking!
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The Big Bang Theory Season 5 Episode 21 Quotes

That's amazing. You'll be like his pit crew.

Leonard

Howard: So, I got the craziest email this morning.
Raj: I hate to burst your bubble, dude, but those penile enlargement pills do not work.
Howard: Believe me I know.