Penny might be the only member of her squad that doesn't have an advanced degree or a firm grasp of string theory and microbiology, but that doesn't mean we should show her any less love. The first lady of "The Big Bang Theory," played by the lovely Kaley Cuoco, is witty, adorable, and chock full of epic Sheldon burns. We're all for watching nerds do their hilarious nerd things on TV, but let's give it up for the always-endearing Penny too. Here are 18 times she was the best part of "The Big Bang Theory."