Barney and his "Vicki Mendoza Diagonal" -- which he actually drew in the air and they showed us!
And wee!goth!Lily is always a delight.
And I could actually understand Audrey's ASL -- and some of Ted's, like "number."
And Bro-da. And Marshall being a "god" and getting Barney to do his laundry. (Marshall: "Who - who are you again?" / Ted: "He's kind of a jackass.")
And non-canon pairings like whoa! Robin/Barney = "sixteen no's," and Ted/Lily.