Amy has a request of Sheldon on the episode "The Desperation Emanation." She wants to introduce him to her mother.
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The Big Bang Theory Season 4 Episode 5 Quotes

When I call him his phone plays Browned Eyed Girl. Which now what I think about it is not so good.

Raj

If they took all the money trying to make a decent Hulk movie, they could probably just make an actual Hulk.

Leonard