Amy: Who's Tam?
Sheldon: He was my best friend in the whole world growing up.
Amy: Really? Why have I never heard you mention him before?
Sheldon: Oh, of course I have. I'm sure I've mentioned him, like, five times this week.
Amy: I don't think you have.
Sheldon: Tam! Tam! Tam! Tam! Tam! There, it's only Thursday.
Amy: I didn't just drink the crazy milk, I bought the crazy cow.