The nerds practice for their NSF expedition to the North Pole by using the Cheesecake Factory's meat locker as a simulation.
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Life isn't much different for the guys in the North Pole as they sit around eating reconstituted Thai food and watching movies.
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Penny gives Leonard a gift... a blanket with sleeves... as his going away present before he leaves to the North Pole.
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The Big Bang Theory Season 2 Episode 23 Quotes

Wolowitz: Just imagine ... if he says yes, we'll have an entire summer without Sheldon.
Raj: We could play outside.
Wolowitz: We could sit on the left side of the couch.
Leonard: I could use the bathroom at 8:20!
Raj: Our dreams are very small, aren't they?

Sheldon: It must be an emergency; everyone at the university knows that I eat my breakfast at 8 and move my bowels at 8:20
Leonard: Yes, how did we live before Twitter?