When Leonard goes to surprise Penny with a trip to Switzerland, he makes her a plate of Swiss hints.
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The Big Bang Theory Season 3 Episode 15 Quotes

Given that St. Valentine was a 3rd century Roman priest who was stoned and beheaded, wouldn't a more appropriate celebration of the evening be taking one's steady gal to witness a brutal murder?

Sheldon

Penny: We're going to Disneyland and ride the Matterhorn?
Leonard: How does that involve air travel?
Penny: We're going to Disney World and ride the Matterhorn?