Almost every day -- usually in the evening -- Sadie plays leap-frog with the dog beds in the living room. If I'm in an adjoining room I'll hear her woof, which means she's play-bowing -- oftentimes to no one in particular. Then I'll hear some panting, which means she's running around in circles. Then she'll run to one of three dog beds in the living room, place her front paws on the bed and pull the bed underneath while simultaneously leaping over it. This will go on for perhaps a minute or two. I say that Sadie is going "crackerdog".
Katie often watches as a spectator from a dog bed not subject to Sadie going crackerdog, although at times she does try to get Sadie to play with her. But on this occasion I caught Katie surveying Sadie's handiwork after she went crackerdog. I think the expression on Katie's face sums up her feelings better than I could describe them in words.