On Thursday night, Christopher Walken told Jon Stewart that he's from Queens, and where he grew up, it's common for police officers to send their kids to tap school. You'll hear the story at the 5:40 mark.
This story sounded awfully familiar, despite how shocked and delighted Jon Stewart seemed. Stewart, in fact, responded like he was hearing it for the very first time, even though ... well. Head to the 2:00 mark.
It just goes to show you: you don't have to have new anecdotes every time. You just have to leave enough space between the tellings, and it's like the story is brand new.
And, of course, when a guy tells you a story you've already heard, you either have to have actually forgotten the last time you heard it, or you have to pretend you did. That's what makes a professional host.