Quote from Barney in The Playbook
Barney: Now, if you don't mind, I'm off to prepare for tonight's main event. I will be performing "the he's not coming". Glad you asked. [title card: "The He's Not Coming". flashback to Barney on the observation deck of the Empire State Building:] Barney: [v.o.] To perform "The He's Not Coming", here's what you'll need, the observation deck of the Empire State Building. Are you up there? Good. For generations, this has been the spot New Yorkers have chosen for their romantic reunions with long-estranged lovers, so all you have to do is walk up to every girl you see and say... Barney: He's not coming. Woman #1: What are you talking about? Barney: Never mind. [to another woman] He's not coming. [Barney gives up when she doesn't respond] [to a third woman] He's not coming. She's not coming? Sorry. Barney: [v.o.] Until sooner or later... Barney: He's not coming. Woman #4: He's not? But we agreed. We always said we'd meet here. On this night. I'm such a fool. [Barney winks to camera]