When Penny locks herself out of the apartment, she comes to hang out with Sheldon in his as he plays Age of Conan. Penny, frustrated by her recent failures in life soon plays and becomes addicted to Conan.
Penny [referring to Sheldon]: What's up with Ichabod? Leonard: Oh, he's trying to make a new friend Penny: Well good for him Leonard: Unless he makes one out of wood like Geppetto, I don't think it's going to happen
Sheldon: I'm a physicist. I have a working knowledge of the entire universe and everything it contains Penny: Who's Radiohead? Sheldon [after twitching for a minute]: I have a working knowledge of the important things