Lily: Oh, here's a good one. "Top Five Things Never to Do Around Robin."
[flashback to Ted's classroom:]
Ted: Three: "Never, ever play the 'Guess Who' game with her."
Barney: What do you mean?
[flashback to spring 2006 as Ted walks up behind Robin on the street and puts his hands over her eyes]
Ted: Guess who?
[Robin pulls Ted's arm and flips him over on to the ground before standing on his chest.]
Ted: It's me! It's me! It's me!